Tea for Heart Health: Studies Show Daily Consumption Reduces Heart Disease Risk
How does tea consumption affect heart health. What types of tea are most beneficial for cardiovascular health. How many cups of tea per day are recommended for heart benefits. What compounds in tea provide protective effects against heart disease.
The Heart-Healthy Benefits of Tea
For millennia, tea has been cherished as a beloved beverage across cultures worldwide. Modern research is now uncovering the powerful health benefits of this ancient drink, particularly when it comes to heart health. Recent studies have demonstrated that regular tea consumption can significantly reduce the risk of heart disease and stroke.
A comprehensive study published in Arteriosclerosis, Thrombosis and Vascular Biology followed over 37,000 people in the Netherlands for 13 years. The findings were remarkable:
- Participants who drank 3-6 cups of tea daily were 45% less likely to die from heart disease compared to those drinking less than 1 cup
- Consuming more than 6 cups per day was associated with a 36% lower risk of developing heart disease
These results highlight the potential for tea to play a significant role in cardiovascular health. But what exactly makes tea so beneficial for our hearts?
Understanding Different Types of Tea
While all true teas offer health benefits, black and green teas have emerged as the leaders in heart health promotion. These teas, along with white and oolong varieties, are derived from the Camellia sinensis plant. The key differences lie in how the leaves are processed:
- White tea: Least processed, made from buds and certain leaves that are steamed and dried
- Green tea: Freshly harvested leaves are immediately steamed to prevent oxidation
- Oolong tea: Allowed to oxidize for a short period
- Black tea: Fully oxidized
These varying degrees of oxidation impact the health-promoting components in each tea type, making them unique in their benefits.
The Power of Green Tea for Cardiovascular Health
Green tea has garnered significant attention in the scientific community due to its high concentration of polyphenols, particularly catechins. Of the six types of catechins found in green tea, epigallocatechin-3-gallate (EGCG) stands out as the most studied and bioactive compound for heart health.
How does EGCG benefit the heart? Recent studies have shown that this powerful antioxidant may help prevent atherosclerosis, especially coronary artery disease. Its anti-inflammatory effects on plaque buildup in the bloodstream and arterial walls can significantly reduce the risk of heart disease and stroke.
Furthermore, green tea catechins work synergistically to lower cholesterol levels. A meta-analysis published in the Journal of the American Dietetic Association found that green tea catechin consumption was associated with a statistically significant reduction in total and LDL cholesterol levels.
Protecting LDL Cholesterol from Oxidation
One of the key mechanisms by which tea protects heart health is by preventing the oxidation of LDL cholesterol particles. When LDL becomes oxidized, it can lead to plaque buildup in the arteries, increasing the risk of atherosclerosis. By protecting LDL from oxidation, tea compounds help maintain healthy arterial function.
Black Tea: A Heart-Healthy Alternative
While green tea often takes the spotlight, black tea also offers significant cardiovascular benefits. Although it may contain fewer polyphenols than its green counterpart, black tea boasts its own unique set of health-promoting compounds.
Black tea is rich in theaflavins and thearubigins, which are formed during the oxidation process. These compounds have been shown to have potent antioxidant properties and may help reduce the risk of heart disease through various mechanisms:
- Lowering blood pressure
- Reducing inflammation
- Improving endothelial function
- Decreasing platelet aggregation
A study published in the European Journal of Clinical Nutrition found that regular consumption of black tea was associated with a significant reduction in cardiovascular risk factors, including blood pressure and lipid profiles.
Optimal Tea Consumption for Heart Health
How much tea should one consume to reap the heart-healthy benefits? While individual needs may vary, research suggests that drinking 3-6 cups of tea per day can provide significant cardiovascular protection.
Is there an ideal time to drink tea for maximum heart benefits? Some studies indicate that consuming tea with meals may enhance its protective effects by reducing the absorption of dietary cholesterol. However, the most important factor is consistency in tea consumption rather than specific timing.
Incorporating Tea into Your Daily Routine
To make tea a regular part of your heart-healthy lifestyle, consider the following tips:
- Start your day with a cup of green or black tea instead of coffee
- Keep a thermos of tea at your desk for easy access throughout the workday
- Enjoy a relaxing cup of herbal tea in the evening to wind down
- Experiment with iced tea varieties during warmer months
- Try different tea blends to keep your palate engaged
Beyond Cardiovascular Health: Additional Benefits of Tea
While the focus of this article is on heart health, it’s worth noting that tea offers a wide range of additional health benefits. Regular tea consumption has been associated with:
- Improved cognitive function and reduced risk of neurodegenerative diseases
- Enhanced weight management and metabolic health
- Stronger immune system function
- Better oral health
- Reduced risk of certain types of cancer
These multifaceted benefits make tea an excellent addition to any healthy lifestyle, with cardiovascular protection being a primary advantage.
Potential Considerations and Precautions
While tea is generally safe and beneficial for most people, there are some considerations to keep in mind:
Caffeine Sensitivity
Tea contains caffeine, which can affect some individuals. Those with caffeine sensitivity or certain medical conditions should consult their healthcare provider about appropriate tea consumption.
Interaction with Medications
Some compounds in tea may interact with certain medications. For example, green tea can interfere with the absorption of iron supplements. If you’re taking any medications, it’s advisable to discuss tea consumption with your doctor.
Quality and Source
To maximize the health benefits of tea, opt for high-quality, organic varieties whenever possible. This can help minimize exposure to pesticides and other contaminants that may be present in lower-quality teas.
The Future of Tea Research and Heart Health
As our understanding of tea’s impact on cardiovascular health continues to grow, researchers are exploring new avenues for harnessing its benefits. Some exciting areas of ongoing research include:
- Development of tea-based nutraceuticals for heart health
- Investigation of specific tea compounds for targeted cardiovascular therapies
- Exploration of tea’s potential in personalized nutrition approaches for heart disease prevention
- Studies on the synergistic effects of tea compounds with other heart-healthy foods
These research efforts may lead to even more targeted recommendations for tea consumption in the context of heart health in the future.
Integrating Tea into a Heart-Healthy Lifestyle
While tea offers significant cardiovascular benefits, it’s important to remember that it should be part of a comprehensive approach to heart health. To maximize the protective effects of tea, consider incorporating it into a broader heart-healthy lifestyle that includes:
- A balanced diet rich in fruits, vegetables, whole grains, and lean proteins
- Regular physical activity
- Stress management techniques
- Adequate sleep
- Limiting alcohol consumption and avoiding tobacco use
By combining regular tea consumption with these lifestyle factors, you can create a powerful synergy for protecting your cardiovascular health.
The Role of Antioxidants in Tea’s Heart-Protective Effects
One of the key mechanisms by which tea promotes heart health is through its high antioxidant content. Antioxidants play a crucial role in protecting our cells from oxidative stress, which is a major contributor to heart disease and other chronic conditions.
How do antioxidants in tea specifically benefit the heart? They work in several ways:
- Reducing inflammation in blood vessels
- Preventing the oxidation of LDL cholesterol
- Improving endothelial function
- Enhancing the body’s overall antioxidant capacity
These effects collectively contribute to a healthier cardiovascular system and reduced risk of heart disease.
The Importance of Consistency in Tea Consumption
While occasional tea drinking can be enjoyable, the true heart-health benefits come from regular, consistent consumption. The cumulative effects of daily tea intake allow the beneficial compounds to build up in the body and exert their protective effects over time.
How can you ensure consistent tea consumption? Consider these strategies:
- Set a daily tea-drinking schedule
- Keep a variety of teas on hand to prevent boredom
- Use a tea tracker app or journal to monitor your intake
- Replace other beverages with tea when possible
By making tea a habitual part of your daily routine, you can maximize its heart-protective potential.
Tea and Blood Pressure Management
High blood pressure is a significant risk factor for heart disease, and tea consumption has been shown to have a positive impact on blood pressure levels. Both green and black teas have demonstrated the ability to help lower blood pressure, making them valuable additions to a heart-healthy diet.
How does tea help regulate blood pressure? Several mechanisms are at play:
- Improving endothelial function, which affects blood vessel dilation
- Reducing inflammation in the vascular system
- Modulating the renin-angiotensin system, which regulates blood pressure
- Providing a natural source of potassium, which helps balance sodium levels
Regular tea consumption, particularly when combined with other lifestyle modifications, can be an effective strategy for managing blood pressure and reducing cardiovascular risk.
Tea’s Impact on Cholesterol Levels
Maintaining healthy cholesterol levels is crucial for heart health, and tea has shown promise in helping to manage cholesterol profiles. Both green and black teas have been associated with improvements in lipid profiles, including:
- Lowering total cholesterol
- Reducing LDL (“bad”) cholesterol
- Increasing HDL (“good”) cholesterol
- Improving the ratio of total cholesterol to HDL cholesterol
These effects are primarily attributed to the catechins and theaflavins found in tea, which help inhibit cholesterol absorption and synthesis in the body.
The Role of Tea in Stress Reduction and Heart Health
Chronic stress is a significant contributor to heart disease, and managing stress is an essential component of cardiovascular health. Tea consumption can play a valuable role in stress reduction, indirectly benefiting heart health.
How does tea help reduce stress and promote relaxation?
- The ritual of preparing and drinking tea can be inherently calming
- L-theanine, an amino acid found in tea, has been shown to promote relaxation without causing drowsiness
- The warmth of tea can have a soothing effect on the body and mind
- Some herbal teas, such as chamomile and lavender, have specific stress-reducing properties
By incorporating tea into your stress management routine, you can create a positive ripple effect that supports overall heart health.
Tea and Weight Management for Heart Health
Maintaining a healthy weight is crucial for cardiovascular health, and tea can be a valuable ally in weight management efforts. Several studies have suggested that regular tea consumption may help support weight loss and prevent weight gain, both of which are beneficial for heart health.
How does tea contribute to weight management?
- Boosting metabolism: The caffeine and catechins in tea can increase energy expenditure and fat oxidation
- Reducing calorie intake: Tea can be a low-calorie alternative to sugary beverages
- Promoting satiety: Some studies suggest that tea may help reduce appetite and increase feelings of fullness
- Supporting gut health: Certain compounds in tea may positively influence the gut microbiome, which plays a role in weight regulation
By supporting healthy weight management, tea consumption can indirectly contribute to improved cardiovascular health.
Tea’s Potential in Diabetes Prevention and Management
Diabetes is a significant risk factor for heart disease, and managing blood sugar levels is crucial for cardiovascular health. Emerging research suggests that tea consumption may have a positive impact on diabetes prevention and management, further supporting its role in heart health.
How might tea benefit those at risk for or managing diabetes?
- Improving insulin sensitivity
- Reducing blood glucose levels
- Decreasing inflammation associated with diabetes
- Protecting pancreatic beta cells, which produce insulin
While more research is needed to fully understand the relationship between tea and diabetes, the potential benefits make it a promising addition to a heart-healthy, diabetes-conscious diet.
The Social Aspect of Tea Drinking and Heart Health
Beyond its physiological benefits, the social aspect of tea drinking may also contribute to heart health. Sharing tea with friends and family can foster social connections, reduce stress, and promote overall well-being – all of which are beneficial for cardiovascular health.
How can you incorporate the social aspects of tea drinking into your life?
- Host regular tea gatherings with friends or family
- Join a local tea club or tasting group
- Use tea breaks as an opportunity for mindful social interaction at work
- Explore different cultural tea traditions and rituals
By embracing both the physical and social benefits of tea, you can create a holistic approach to supporting your heart health.
Tea’s Good for the Heart — Studies Show a Few Cups a Day Keep Heart Disease at Bay
March 2013 Issue
Tea’s Good for the Heart — Studies Show a Few Cups a Day Keep Heart Disease at Bay
By Lori Zanteson
Today’s Dietitian
Vol. 15 No. 3 P. 18
There’s nothing like having a hot cup of tea to jump-start your morning or a tall glass of iced tea to cool you off in the summertime.
For more than 5,000 years, various peoples and cultures across the globe have enjoyed drinking tea, making it the most consumed beverage second only to water. Fortunately, our tea-drinking ancestors had the wisdom to recognize its value and the foresight to continue the tradition of enjoying this elixir that we now know has powerful health benefits. One of the many known benefits uncovered by modern research: High tea consumption leads to a healthier heart.
Upbeat Findings
According to data published in 2012 in Food & Function, black and green tea may reduce the risk of coronary heart disease and stroke by 10% to 20%.1 Two years before, one of the largest studies on the impact of tea drinking on heart health was published in Arteriosclerosis, Thrombosis and Vascular Biology. The study followed more than 37,000 people in the Netherlands for 13 years and found that people who drink plenty of tea are less likely to die of heart disease than people who don’t drink tea. Study participants who drank three to six cups of tea per day were 45% less likely to die from heart disease than those who drank less than one cup, and drinking more than six cups of tea per day was associated with a 36% lower risk of developing heart disease than drinking less than one cup. 2
Tea Defined
While all four types of tea known as true teas—white, green, oolong, and black—offer myriad health benefits, most studies show that black and green teas are the heart-health leaders. Each tea type is made from the leaves of the evergreen shrub Camellia sinensis, but the differences between them are due to the ways in which they’re processed into individual varieties.
White tea is the least processed and is made from buds and certain leaves of the Camellia sinensis plant, which are steamed and dried. Green tea is produced from freshly harvested leaves, which immediately are steamed to prevent oxidation or oxygen exposure. Oolong tea is allowed to oxidize for a short period, and black tea is completely oxidized. The results of the varying degrees of oxidation affect the health-promoting components, which make each type of tea unique.
Go Green
The steaming process of green tea destroys the enzymes that break down the color pigments in the leaves, allowing them to maintain their green color. The leaves then are rolled and dried, preserving their natural polyphenols, the potent antioxidants.
Most of the polyphenols in green tea are in the form of flavonoids, specifically known as catechins, the plant chemicals responsible for green tea’s heart-healthy properties. Because of the differences in processing, green tea contains the most catechins of the other tea varieties. Of the six types of catechins in green tea, epigallocatechin-3-gallate (EGCG) is the most studied and most bioactive for heart benefits.
Several recently published studies, such as one in the July 2012 issue of Pharmacological Reports, show that the powerful antioxidants in green tea, particularly EGCG, may help prevent atherosclerosis, specifically coronary artery disease, because of their anti-inflammatory effects on plaque buildup in the bloodstream and arterial walls, which can lead to heart disease and stroke.3
Green tea catechins also work together to lower cholesterol. A systematic review and meta-analysis in the November 2011 issue of the Journal of the American Dietetic Association reported that of the 20 randomized controlled trials evaluated, “the consumption of green tea catechins is associated with a statistically significant reduction in total and LDL cholesterol levels.”4
In addition to lowering inflammation in the bloodstream and reducing LDL cholesterol, tea protects LDL particles from becoming oxidized, which causes plaque buildup in the arteries and can lead to atherosclerosis, according to Janet Bond Brill, PhD, RD, LDN, CSSD, an expert on food and fitness for heart health and the author of several books, including the forthcoming Blood Pressure Down: The 10-Step Plan to Lower Your Blood Pressure in 4 Weeks Without Prescription Drugs.
In the Black
Black tea may not have as many polyphenols as its green counterpart, but the changes in its polyphenols during the oxidation process produce a set of unique compounds that have their own heart-health benefits. In fact, a 2012 study published in Preventive Medicine found that drinking three cups of black tea per day for 12 weeks led to significant reductions in blood sugar levels and triglycerides, an increase in HDL cholesterol levels, and increased blood levels of antioxidants, which can protect against oxidative stress and inflammation.5
Other research, such as a 2012 study reported in Archives of Internal Medicine, has shown black tea improves endothelial function and blood pressure. This study found that drinking three cups of black tea per day for six months lowered both systolic and diastolic blood pressure, which the report said could reduce the risk of cardiovascular disease.6
Herbal Teas
Even though green, white, oolong, and black teas pack the most powerful antioxidant punch, herbal teas still are a healthful option, according to Emily Bailey, RD, LD, who oversees the corporate wellness program for the Republic of Tea and is director of nutrition coaching at NutriFormance-Fitness, Therapy, and Performance in St Louis. “Herbal teas have lower concentrations of antioxidants because the chemical composition varies widely among the different plants” from which they’re made, she explains. Rooibos, or red tea, made from the South African plant Aspalathus linearis, has been shown to have heart benefits, such as in a 2011 study where volunteers drank six cups of rooibos tea per day for six weeks and experienced reduced LDL cholesterol and significantly increased HDL cholesterol, both associated with a lower risk of developing cardiovascular disease.7
A common ingredient in many herbal tea blends, hibiscus tea (or tisane) also may be good for the heart. A 2010 study showed that six weeks of drinking hibiscus tea each day lowered blood pressure in pre- and mildly hypertensive adults, which may make it a heart-healthy dietary addition for this group of people.8
Herbal teas may be especially relevant for those who don’t like green or black teas; the key is to drink it frequently. “The jury is still out on how much tea should be consumed, but adding any to your typical intake can be very beneficial,” Bailey says. Whether you steep it yourself—Consumer Reports found that tea steeped from bags had the highest antioxidant levels—or choose bottled varieties, Bailey says it’s important to choose the “whole, real food first.”
“As an RD, the body of research supports eating the food rather than the supplement,” Brill says. “The bulk of research supports the people who drink quite a bit of tea.” Popping tea supplements may be tempting if the thought of drinking tea all day seems impossible, but frequency, a little creativity, and variety is all it takes, she says.
Steep Often
To maximize the beneficial effects of tea, Brill recommends enjoying it throughout the day. “It functions as an antioxidant, so keep a high level in your bloodstream,” she explains. Studies support that timing is important to reap green tea’s benefits. A 2004 study in Circulation found that when mice were fed a high cholesterol diet and then were injected with green tea extract, they had 55% less plaque in their arteries after three weeks and 73% less after six weeks.9 A 2008 Greek study found that when people drank green tea they had better blood vessel function just 30 minutes later, which helps prevent atherosclerosis.10
Drink tea “several times a day and learn to do it in different ways,” Brill says, “[for example] instead of water, drink iced tea.” Hot or cold, the benefits are the same, but she suggests drinking it without milk, which can blunt the favorable effect on the arteries. On the other hand, feel free to add a squeeze of lemon juice, which is a source of vitamin C, to add an extra health boost to your cup.
— Lori Zanteson is a freelance food, nutrition, and health writer and editor based in southern California.
References
1. Bøhn SK, Ward NC, Hodgson JM, Croft KD. Effects of tea and coffee on cardiovascular disease risk. Food Funct. 2012;3(6):575-591.
2. de Koning Gans JM, Uiterwaal CS, van der Schouw YT, et al. Tea and coffee consumption and cardiovascular morbidity and mortality. Arterioscler Thromb Vasc Bio. 2010;30(8):1665-1671.
3. Li M, Liu JT, Pang XM, Han CJ, Mao JJ. Epigallocatechin-3-gallate inhibits angiotensin II and interleukin-6-induced C-reactive protein production in macrophages. Pharmacol Rep. 2012;64(4):912-918.
4. Kim A, Chiu A, Barone MK, et al. Green tea catechins decrease total and low-density lipoprotein cholesterol: a systematic review and meta-analysis. J Am Diet Assoc. 2011;111(11):1720-1729.
5. Bahorun T, Luximon-Ramma A, Neergheen-Bhujun VS, et al. The effect of black tea on risk factors of cardiovascular disease in a normal population. Prev Med. 2012;54 Suppl:S98-S102.
6. Hodgson JM, Puddey IB, Woodman RJ, et al. Effects of black tea on blood pressure: a randomized controlled trial. Arch Intern Med. 2012;172(2):186-188.
7. Marnewick JL, Rautenbach F, Venter I, et al. Effects of rooibos (Aspalathus linearis) on oxidative stress and biochemical parameters in adults at risk for cardiovascular disease. J Ethnopharmacol. 2011;133(1):46-52.
8. McKay DL, Chen CY, Saltzman E, Blumberg JB. Hibiscus sabdariffa L. tea (tisane) lowers blood pressure in prehypertensive and mildly hypertensive adults. J Nutr. 2010;140(2):298-303.
9. Chyu KY, Babbidge SM, Zhao X, et al. Differential effects of green tea–derived catechin on developing versus established atherosclerosis in apolipoprotein E-null mice. Circulation. 2004;109(20):2448-2453.
10. Alexopoulos N, Vlachopoulos C, Aznaouridis K, et al. The acute effect of green tea consumption on endothelial function in healthy individuals. Eur J Cardiovasc Prev Rehabil. 2008;15(3):300-305.
Tea and Cardiovascular Disease
Pharmacol Res. Author manuscript; available in PMC 2012 Aug 1.
Published in final edited form as:
PMCID: PMC3123419
NIHMSID: NIHMS286623
Evans Department of Medicine and the Whitaker Cardiovascular Institute, Boston University School of Medicine, Boston, MA
Address for Correspondence: Joseph A. Vita, MD, Professor of Medicine, Boston University School of Medicine, 88 East Newton Street, C-818, Boston, MA 02118, 1-617-638-8742, 1-617-638-8712 (FAX), ude.ub@ativjThe publisher’s final edited version of this article is available at Pharmacol ResSee other articles in PMC that cite the published article.
Abstract
There is increasing evidence for a protective effect of tea consumption against cardiovascular disease. This review summarizes the available epidemiological data providing evidence for and against such an effect. We also review observational and intervention studies that investigated an effect of tea and tea extracts on cardiovascular risk factors, including blood pressure, serum lipids, diabetes mellitus, and obesity. Finally, we review potential mechanisms of benefit, including anti-inflammatory, anti-oxidant, and anti-proliferative effects, as well as favorable effects on endothelial function. Overall, the observational data suggest a benefit, but results are mixed and likely confounded by lifestyle and background dietary factors. The weight of evidence indicates favorable effects on risk factors and a number of plausible mechanisms have been elucidated in experimental and translational human studies. Despite the growing body evidence, it remains uncertain whether tea consumption should be recommended to the general population or to patients as a strategy to reduce cardiovascular risk.
Keywords: Tea, polyphenols, catechins, flavonoids, cardiovascular disease, endothelium
1. Introduction
Tea leaves are obtained from the Camillia Sinensis plant. Based on how the leaves are processed, three main types of tea can be produced: non-fermented green tea, partly-fermented oolong tea and fermented black tea. Records from as far back as the 10th century BC indicate use of tea by man, largely because of its medicinal value. This review will focus on possible beneficial effects against cardiovascular disease
Tea leaves contain a large amount of polyphenols (about 30% of the dry substance), mainly flavonoids. The major class of flavonoids in tea are flavanols, which include catechin, epicatechin (EC), epigallocatechin (EGC), epicatechin gallate (ECG), and epigallocatechin gallate (EGCG) [1]. Total polyphenol content is similar in different types of tea, but the individual components vary, based in part on the degree of polyphenol oxidation during the manufacturing process. Catechins constitute about 80–90% and flavanols about 10% of the total flavonoids in green tea. On the other hand, theaflavins account for 50–60% and catechins only 20–30% of total flavonoids in black tea [2].
Recently, there has been considerable interest in the possibility that consumption of tea reduces risk for cardiovascular disease. Some observational studies suggest a benefit of tea, while other studies have failed to show such an association. Mechanistic studies have shown that tea and tea polyphenols have favorable effects on systemic risk factors and direct effects on the vasculature and platelets that might account for reduced cardiovascular risk. In the following sections, we will summarize the supportive and non-supportive observational studies that investigated a relationship between tea consumption and cardiovascular risk. We will then consider experimental, mechanistic and translational studies that elucidate potential mechanisms of benefit. Finally, we will attempt to put these data into clinical context given the considerable interest in dietary and lifestyle approaches to reduce cardiovascular disease.
2. Epidemiologic studies with tea and cardiovascular disease events
A large number of cross-sectional and prospective outcome studies investigated the relation between tea consumption and cardiovascular disease. In addition several meta-analyses have been performed that pool these data. Overall, the evidence suggests a benefit, for both green and black tea, but the results may be confounded by lifestyle and other dietary factors.
Nearly all of the published studies examining the relation between green tea consumption and cardiovascular risk suggest a reduction in risk. In an early study from Japan, Sato and colleagues followed a cohort of 5,910 women for four years and found that the incidence of stroke and cerebral hemorrhage was two times higher in those with daily green tea consumption less than five cups when compared to those with more than five cups [3]. More recent studies also showed a beneficial effect of green tea consumption in Japan. Nakachi and colleague studied a cohort of 8,552 participants and observed a 28% reduction in death from cardiovascular disease for men and women consuming over 10 cups a day compared to those consuming less than 3 cups per day [4]. Similarly, the Ohsaki National Health Insurance Cohort Study, which followed 40,530 Japanese adults for 11 years, demonstrated a dose relationship between increasing green tea consumption and reduced total and cardiovascular mortality that was strongest in women with a relative risk of 0.69 (95% CI, 0.53–0.90) for women who consumed more than five cups per day [5]. Stroke mortality was particularly reduced in tea drinkers. A case-control study from China also suggested a favorable effect of green and oolong tea consumption against ischemic stroke [6].
Recently, a very large prospective study involving 76,979 Japanese adults examined the relationship between cardiovascular mortality and consumption of several different types of tea. The investigators reported a strong inverse relationship between cardiovascular mortality and consumption of more then six cups of green tea per day [7]. Interestingly, consumption of more than one cup of oolong tea per day was also associated with reduced risk in Japan [7]. Overall, these studies conducted in Japan and China suggested that consumption of relatively large amounts of green tea (5 to 10 cups per day) is associated with reduced cardiovascular events.
Studies performed in Europe and the U.S. suggested a benefit from consumption of black tea. For example, Sesso and colleagues completed a case-control study and observed that individuals with history of myocardial infarction were less likely to be consuming more than a cup of black tea per day compared to age, sex, and community-matched controls (odds ratio of 0.56) [8]. In the Determinants of Myocardial Infarction Onset Study, individuals consuming more than an average of two cups of black tea per day had lower total and cardiovascular mortality during 3.8-year follow-up compared to individuals consuming less tea [9]. The same study demonstrated lower prevalence of ventricular arrhythmia during hospitalization for myocardial infarction among tea drinkers, possibly suggesting less severe infarction and providing a potential explanation for the reduction in cardiovascular mortality observed during subsequent follow-up [10].
A large cohort of 37,514 participants in Netherlands was prospectively followed for 13 years with end points of cardiovascular disease morbidity and mortality [11]. In that study, consumption of tea (mainly black tea) 3 to 6 cups daily was associated with a reduced risk of cardiovascular disease mortality. There was no association, however, between tea consumption and all cause mortality. In that study, tea drinking was found to also be associated with a higher educational level, higher physical activity, healthier diet, and lower prevalence of smoking, hypercholesterolemia and diabetes. Although the investigators adjusted for these factors, residual confounding by health behavior could have affected the results. A study from a Norwegian cohort (Oppland County) of 9,856 men and 10,233 women showed a strong trend for a benefit of tea [12]. In that study, there were significant correlations between tea consumption and blood pressure and cholesterol levels, which were lower among individuals consuming one or more cups of tea per day.
Several epidemiological studies failed to show an association between tea consumption and cardiovascular disease. For example, in the Scottish Heart Health Study involving 10,359 men and women there was no association between tea consumption and prevalent coronary heart disease [13]. In a cohort of 1,900 Welsh men, the group with the highest consumption of tea (more than eight cups per day) actually had higher ischemic heart disease mortality compared to the group consuming less than two cups per day [14]. The authors pointed out that tea is often consumed with milk in the United Kingdom and speculated that milk might have affected absorption or increased fat intake and influenced a benefit of tea.
Other factors might explain the lack of benefit in these studies. For example, it has been noted that tea consumption is more common among individuals of low socioeconomic status in the U.K., and the association between lower social status and higher cardiovascular disease risk might obscure a beneficial effect of tea [15]. Another consideration is the baseline flavonoid intake. If the entire U.K. population has a relatively high level of tea intake, then even individuals in the lower range of consumption could be receiving the maximal benefits of tea. Conversely, a study in cohort with relatively low overall tea intake might fail to show a benefit even in the subgroup of individuals in the highest quartile or quintile of tea intake. In this regard, the relationship between tea consumption and cardiovascular events was only a non-significant trend (P=0.07) in the Women’s Health Study, where only a small proportion of the women in the U.S. consumed more than four cups of tea per day [16]. Sesso and colleagues also observed no significant association between tea consumption and cardiovascular disease in a cohort of 17,228 college alumni (College Alumni Health Study) where the median intake of tea was relatively low (1 cup per day) [17]. This cohort also was relatively healthy and had higher socioeconomic status than some of the other studies, which also may have made it difficult to show a benefit of tea consumption. Such factors might also account for the lack of benefit of tea consumption in a cohort of 34,789 male health professionals [18].
Overall, the bulk of evidence does suggest that higher consumption of both green and black tea is associated with reduction of cardiovascular risk, despite the negative results of some studies. A number of meta-analyses have been performed to more formally address this question. For example, Peters and colleagues examined the relation of tea consumption to stroke, myocardial infarction, and all coronary heart disease in an analysis of 10 cohort studies and seven case-control studies [19]. The incidence of myocardial infarction was estimated to be 11% lower for an increase in tea consumption of 3 cups per day (1 cup= 237 ml). Those investigators, however, acknowledged that their results need to be interpreted with caution because there was evidence of bias toward preferential publication of smaller positive studies [19]. Also, there was heterogeneity that could be explained by the geographic region where the studies were conducted. The same group pooled data from nine studies involving 194,965 individuals and concluded that consumption of three or more cups of green or black tea per day was associated reduced incidence of ischemic stroke [20].
In regard to the specific components of tea that are responsible for benefit, several epidemiological studies and meta-analyses have examined consumption of flavonoid-containing foods more generally. In addition to tea, such foods include grapes and red wine, chocolate, apples, onions, and other fruits and vegetables. In the Zutphen Elderly Study, which examined a cohort of 805 Dutch men with five-year follow-up, dietary flavonoids were inversely associated with coronary heart disease mortality with relative risk of 0.42 for individuals in the highest versus lowest tertile of flavonoid intake [21]. A similar relationship was observed after 10-year follow-up that remained highly significant after adjustment for cardiovascular risk factors [22]. Flavonoid intake also was inversely related to stroke in the same cohort [23]. In the Seven Countries Study with 25 years of follow-up, there was an inverse correlation between flavonoid intake and incidence of coronary heart disease [24]. In a Finnish cohort of 25,372 male smokers, flavonol and flavone intake was inversely associated with myocardial infarction and there also was a trend for reduced coronary heart disease death [25].
In contrast, there was no significant correlation between flavonoid intake and cardiovascular disease events in a cohort of U.S. women participating in the Women’s Health Study [16], but as previously noted, overall flavonoid intake in this cohort was relatively low. Overall, available evidence, including several meta-analyses suggests a benefit of flavonoid consumption against cardiovascular disease [26,27]
3. Tea and risk factors for cardiovascular disease
Given the apparent association between tea consumption and cardiovascular disease events, it is worthwhile to consider the potential mechanisms of benefit. One important potential mechanism is direct effect of tea on cardiovascular disease risk factors. A large number of epidemiological and intervention studies have examined this issue. Despite this large body of work, it remains unclear whether tea consumption has favorable effects on blood pressure, serum lipids, diabetes mellitus, or obesity in human subjects. If present, the beneficial effects of tea on risk factors are likely to be modest.
3.1 Hypertension
Epidemiological and intervention studies provide evidence that consumption of tea and other polyphenol-containing foods lower blood pressure. In a large epidemiological study involving over 20,000 Norwegian participants, systolic blood pressure was 2.1 and 3.5 mmHg lower in men and women, respectively, who consumed five or more cups of tea per day [12]. In a study of 218 elderly women, tea consumption and urine 4-O-methylgallic acid (a measure of polyphenol consumption) correlated inversely with systolic and diastolic blood pressure, with a 2.2 mmHg lower systolic blood pressure for each cup of tea consumed [28]. While these absolute changes in blood pressure may seem small, changes of this magnitude on a population basis would result in the prevention of many cardiovascular events and strokes [29]. Yang and colleagues examined incident hypertension in a cohort of 1,507 men and women in Taiwan and observed a reduction in the risk of developing new hypertension in individuals consuming more than 120 ml of green or oolong tea per day after adjusting for other risk factors, lifestyle, sodium intake, and coffee consumption [30]. On the other hand several very large studies have shown no relation between tea consumption and blood pressure [31–33].
Intervention studies provide additional information about the effects of tea consumption on blood pressure. This question is complicated because, in addition to flavonoids, tea contains caffeine, which causes a short-term increase in blood pressure. Hodgson observed an increase in blood pressure 30 min after ingestion of green or black tea in normotensive men that was no longer evident at 60 minutes after [34]. Interestingly, this increase in blood pressure was actually greater than the effect of an equivalent dose of caffeine alone suggesting that tea or tea polyphenols might cause acute increases blood pressure. Consumption of either form of tea for seven days had no effect on 24-hour ambulatory blood pressure in the same population [34]. The same group of investigators observed that the acute hypertensive effect of tea consumption was blunted when tea was consumed with food [35].
Nagao and colleagues completed a study of green tea extract (583 mg of catechin) in Japanese men and women with abdominal obesity [36]. In the subgroup of participants with baseline systolic blood pressure of 130 mmHg or higher, tea extract significantly reduced blood pressure compared to placebo [36]. Brown and colleagues examined the effects of EGCG on blood pressure and other metabolic risk factors in overweight or obese men and observed a 2.7 mmHg reduction in diastolic blood pressure [37]. More recently, Nantz and colleagues completed a double-blind trial in 111 healthy volunteers comparing the effects of a standardized capsule containing 200 mg of decaffeinated catechin green tea extract to placebo [38]. They observed a 5 mmHg decrease in systolic blood pressure that was significantly different from the effect of placebo.
The apparently favorable effects of tea and tea components on blood pressure in intervention studies contrast with the results of a large number of other clinical studies examining the effects of tea on a variety of physiological endpoints. Taubert and colleagues recently completed a meta-analysis pooling five parallel group and cross-over studies that reported on the effects of tea on blood pressure in a total of 343 participants with a median duration of four weeks [39]. The meta-analysis revealed no significant effect of tea consumption on blood pressure. Interestingly, they did observe a favorable effect of chocolate consumption on blood pressure using the same approach.
Overall, the available studies do not provide a definitive answer to the question of whether tea consumption lowers blood pressure. Many of the studies examined normotensive populations and populations already well controlled on anti-hypertensive therapy, where it is difficult to demonstrate a blood pressure lowering effect with any intervention. Furthermore, few of the studies used 24-ambulatory blood pressure monitoring or treated subjects for an extended period of time. Any benefit of tea flavonoids must overcome the short-term blood pressure raising effects of caffeine. Thus, despite the large number of prior epidemiological and interventional studies, further definitive studies are needed to determine the acute and chronic effects of tea consumption on blood pressure in patients with hypertension and whether blood pressure effects could explain the observed associations between tea consumption and reduced cardiovascular risk.
3.2 Dyslipidemia
Improvement in serum lipid profile is another possible mechanism that would account for a beneficial effect of tea on cardiovascular disease, and several observational studies suggest that tea might have such an effect. Kono and colleagues reported that total serum cholesterol was 8 mg/dl lower in 1,306 Japanese men consuming nine or more cups of green tea per day [40]. Stensvold reported a comparable reduction in total cholesterol in Norwegian men and women consuming more than five cups of black tea per day [12]. On the other hand, several observational studies have shown no relationship between green or black tea consumption and total or LDL cholesterol levels [41,42].
The question of a lipid-lowering effect of tea has also been examined in randomized intervention studies that allow for control of potential confounding variables. Davies and colleagues completed a placebo controlled, double blind crossover study of five cups of black tea and placebo beverage in 15 mildly hypercholesterolemic adults and observed a reductions of 6.5% and 11.1% in total and LDL cholesterol, respectively [43]. In a much larger (n=240) and well-designed randomized crossover study, Maron and colleagues observed comparable reductions in LDL cholesterol with consumption of flavin-enriched green tea for 12 weeks [44]. Several other intervention studies have shown cholesterol lowering effects of green and black tea as well as tea extracts [38,45–48] Other studies have failed to show such an effect [37,49–51]. Interestingly, there is evidence that tea consumption may have a favorable effect on post-prandial lipids, which are particularly atherogenic [45] and a favorable effect on HDL cholesterol in patients with diabetes mellitus [52].
Overall, the published studies examined many different patient populations with varying degree of baseline dyslipidemia and background therapy. The available studies also examined many different preparations and extracts of tea. This heterogeneity in study design likely explains the divergent results. In an extensive meta-analysis involving 133 interventions studies examining the effects of various flavonoid-containing foods, Hooper and colleagues concluded that green tea consumption has significant albeit modest LDL lowering effect [53].
1.3.3 Diabetes and obesity
Type 2 diabetes mellitus is a major cardiovascular disease risk factor and is increasing in prevalence, in large part due to the ongoing obesity epidemic [54]. Insulin resistance is the primary pathophysiological mechanism in type 2 diabetes mellitus, and there is experimental evidence that polyphenols found in tea can improve insulin sensitivity. Observational and intervention studies suggest that this mechanism may be operative in humans. In a study of 17,413 Japanese adults, Iso and colleagues reported that the incidence of new diabetes was inversely associated with consumption of more than six cups of green tea per day, while there was no association with black or oolong tea [55]. Interestingly, there also was an inverse association between diabetes mellitus and coffee consumption in that study. Greenberg and colleagues observed that consumption of two cups of “regular tea” (presumably black tea) per day was associated with a reduction in the incidence of diabetes during an 8.4 year follow-up period in participants of the National Health and Nutrition Examination Survey (NHANES) who were age 60 or younger [56]. On further subgroup analysis, this relationship applied to the individuals who had lost weight during the follow-up period. The Whitehall II study also showed decreased incidence of diabetes mellitus in 5,823 participants followed for 11.7 years that was not significant after adjustment for concomitant risk factors [57]. Finally, in the Women’s Health Study, Song and colleagues observed a borderline significant relationship between tea consumption (≥4 cups day) and the incidence of new diabetes mellitus over an 8 year follow-up period with a relative risk of 0.72 (95% CI 0.52 – 1.01) [58].
In contrast, several very large studies showed no relationship. For example, in reports from the Nurses Health Study and Health Professionals’ Follow-up Study, there was no significant relation between tea consumption, although interestingly there was a relationship with coffee consumption [59,60]. There also was no relation between tea consumption and diabetes in a large cohort of 46,906 African American Women [61]. Despite these negative studies, Huxley and colleagues completed a meta-analysis examining the effects of caffeinated beverages on incident diabetes combining data from 18 studies with information from nearly half a million individuals [62]. In regard to tea, they found that overall the relative risk of new diabetes was significantly reduced (RR 0. 84, 95% CI 0.73 – 0.94).
As for the other risk factors discussed above, clinical intervention studies examining the effects of tea and tea polyphenols on endpoints related to diabetes provide additional insight into the question of whether tea might affect diabetes mellitus. Hosoda and colleagues observed that consumption of oolong tea (1,500 ml/day) for 30 days in a placebo controlled crossover study lowered fasting glucose in 20 patients with type 2 diabetes mellitus on hypoglycemic drugs [63]. Consumption of one gram of black tea by healthy volunteers lowered the blood glucose and blood insulin responses to an oral glucose load (glucose tolerance test) suggesting an improvement in insulin sensitivity [64].
In contrast, Fukino and colleagues completed a placebo controlled study examining the effects of green tea (administered as a extract powder containing 544 mg polyphenols mixed with hot water) in a group of 66 patients with diabetes mellitus or borderline diabetes [65]. Compared to the effects of placebo, there were no effects of green tea on measures of glycemic status, including blood glucose, insulin, hemoglobin A1C, or the homeostasis model assessment of insulin resistance (HOMA-IR). Interpretation of this study is complicated by a relatively similar intake of polyphenols in the active (747 mg/d) and placebo (469 mg/d) groups and the observation that these glycemic variables improved in both the active and placebo groups. It is possible that an effect of green tea would have been detected if polyphenol intake had been limited in the placebo group, as is often done in studies of this type. Ryu and colleagues also observed no effect of green tea consumption compared to water in a crossover for four weeks in 55 patients with type 2 diabetes mellitus.
Interestingly, there have been studies showing an effect of tea consumption on body weight. For example, Chantre and colleagues administered green tea extract to moderately obese subjects for 3 months observed a 4. 6% decrease in body weight and 4.5% decrease in waist circumference by 4.48% [66]. In a study of 38 healthy Japanese men with normal body mass index randomized to consume green tea or a low catechin control, Nagao and colleagues reported that green tea consumption produced a 2.4 kg decrease in body weight and favorable effects on waist circumference, body fat mass, skin-fold thickness, and total subcutaneous fat areas (tested by computed tomography) [67]. The same group subsequently completed a larger randomized, placebo-controlled study in 240 Japanese men and women and observed a 1.7 kg decrease in body weight and significant changes in body fat and fat distribution with consumption of green tea extract [36]. Recently, Basu and colleagues showed a decrease in body weight following eight weeks of green tea or green tea extract compared to placebo in a group of 35 obese individuals with the metabolic syndrome [49]. The mechanisms accounting for weight loss with tea or tea components remain unclear. It has been suggested that they may increase sympathetic nervous system activity and stimulate thermogenesis, which would increase calorie consumption [68].
As for other risk factors, the available studies provide inconsistent findings. Some studies showed weight loss and reduction of diabetes, while others did not. Differences in study population and tea preparation likely explain these inconsistencies. Overall, the available evidence, including a large meta-analysis, suggests that tea consumption reduces the incidence of new diabetes mellitus. There is a modest level of evidence supporting a favorable effect of tea components on insulin sensitivity. Finally, tea consumption appears to induce a modest amount of weight loss. These conclusions must be tempered by the possibility of publication bias and the relatively small size of most of the published intervention studies.
4. Mechanistic studies with tea and cardiovascular diseases
Experimental and translational clinical studies have provided further insight into the mechanisms of benefit for tea against cardiovascular disease and contains a partial list of such mechanisms. These include antioxidant effects, anti-inflammatory effects, and improvement of endothelial function. This section will review these possible mechanisms.
Table 1
Potential Mechanisms of Benefit for Tea Against Cardiovascular Disease
Blood pressure lowering |
Improved dyslipidemia |
Improved insulin sensitivity |
Weight loss |
Antioxidant effects – scavenging reactive oxygen species and preventing oxidation of lipids, proteins, and DNA |
Anti-inflammatory effects |
Improved endothelial function |
Platelet inhibition |
Inhibition of smooth muscle cell proliferation and migration |
4.
1. Antioxidant effects of tea and tea components
According to the oxidative hypothesis of atherosclerosis, LDL oxidation is a key step in the atherogenic process [69]. Based this hypothesis, considerable effort was made to determine whether antioxidant compounds that inhibit LDL oxidation might prevent cardiovascular disease in humans [70]. A large number of studies, including large clinical trials were conducted, and overall there remains little evidence that antioxidant supplements, including vitamins E and C and beta carotene, reduce cardiovascular disease. While it is clear that atherosclerosis is associated with increased oxidative stress, it is now understood that reactive oxygen species play important signaling roles in the vasculature and that simply scavenging reactive oxygen species or inhibiting LDL oxidation is not an effective strategy to inhibit atherosclerosis [71]. In this context, it is known that tea polyphenols have antioxidant effects in vitro [72–75] and many studies sought evidence for antioxidant effects of tea in humans.
In regard to in vitro effects, tea and tea extracts have been shown to scavenge superoxide and other reactive oxygen species [76]. Tea and tea components have also been shown inhibit lipid peroxidation [75,77–80]. Furthermore, exposure of isolated endothelial cells to tea limits their ability to oxidize LDL [81]. Tea flavonoids can chelate redox active metal ions, which limits production of reactive oxygen species via the Fenton reaction [82]. There is animal evidence for antioxidant effects of tea following oral administration [83–85]. Consistent with the more recent human data, green and black tea inhibited LDL oxidation following oral administration to hypercholesterolemic rabbits, but the effect did not relate to changes in extent of atherosclerosis [84].
As mentioned, studies show that tea influences plasma antioxidant status in humans. For example, several studies have shown that tea consumption increases the ability of plasma to scavenge reactive oxygen species [46,86,87]. Studies have also shown that LDL isolated from plasma is less susceptible to oxidation following tea consumption [88], while other studies have failed to show such an effect [51,75,87,89,90]. In regard to preventing oxidation of lipids, proteins, or DNA in vivo, the evidence for beneficial effects of tea are less clear. Hakim and colleagues reported that green tea, but not black tea, by cigarette smokers decreased urinary levels of 8-hydroxy-deoxyguanosine, a marker of DNA oxidation [91]. Klaunig and colleagues reported a similar finding [92]. Erba and colleagues reported a reduction of DNA oxidative damage in lymphocytes isolated from healthy volunteers [46]. Other studies failed to show evidence that consumption of tea inhibits markers of lipid or DNA oxidation in human subjects [90,93,94].
As was observed in intervention studies examining the effects of tea consumption on risk factors, the data are mixed regarding antioxidant effects of tea consumption. Some of the discrepant results may reflect differences in tea preparations and the studied populations. Overall, there are reasonably convincing studies to indicate that consumption of tea or tea components can influence antioxidant capacity plasma. However, the bulk of the evidence does not support an in vivo antioxidant effect following consumption of relevant amounts of tea.
4.2 Anti-inflammatory effects
Inflammation is now known to be an integral part of atherosclerosis and is involved from the earliest stages of atherogenesis to later stages of plaque vulnerability and rupture, which causes clinical events such as myocardial infarction and stroke [95]. There is strong evidence in experimental models and in animals that suggest anti-inflammatory effects of tea and tea components. In vitro studies have shown favorable effects on inflammatory cells. For example, EGCG inhibits migration of neutrophils through an endothelial cell monolayer [96], decreases the activity of neutrophil elastase [97], and reduces ROS production and chemokine-induced chemotaxis of neutrophils [98,99]. EGCG also inhibits adhesion and migration of CD8+ T cells [100]. EGCG and other catechins have been shown to inhibit cytokine-induced adhesion molecule expression and monocyte adhesion in cultured endothelial cells [101]. EGCG blocked lipopolysaccharide-induced tumor necrosis factor alpha (TNF-alpha) production and lethality in mice [102] and had reduced inflammatory activation in the lung in a mouse model of pulmonary fibrosis [103].
In humans, epidemiological and intervention studies have examined anti-inflammatory effects of tea consumption. Serum levels of C-reactive protein and other markers of inflammation relate strongly to cardiovascular risk, and several epidemiological studies examined the effects of tea consumption on such markers. For example, tea consumption was inversely related to C-reactive protein levels in a cohort of 1031 health men [104]. Other studies failed to show such a relationship [58,105,106]. More generally, flavonoid consumption and fruit and vegetable consumption are associated with lower levels of C-reactive protein [107,108], making it harder to confirm a specific relationship with tea consumption.
In regard to intervention studies, Neyestani and colleagues reported a decrease in C-reactive protein following consumption of black tea extract for four weeks in 46 patients with type 2 diabetes mellitus [109]. Steptoe and colleagues also reported a decrease in C-reactive protein and pro-inflammatory monocyte-platelet aggregates following four weeks of black tea consumption in healthy men [110]. Green tea consumption reduced C-reactive protein levels in male smokers [111]. Other well-done studies, however, showed no such effects in patients with risk factors or coronary artery disease [65,90,112,113].
As has been observed for other tea intervention studies, the discrepant results are likely attributable to differences in tea preparations and patient characteristics. No formal meta-analysis has examined the effects of tea consumption on C-reactive protein or other markers of inflammation. However, the bulk of the evidence does not suggest a strong anti-inflammatory effect of tea consumption, despite promising experimental studies.
4.3. Endothelial function
The endothelium is a major regulator of vascular homeostasis and controls arterial tone, thrombosis, the composition of the arterial wall, and local inflammation by production of a variety of factors, including nitric oxide nitric oxide [114]. Abnormalities of endothelial function relate to cardiovascular risk factors, predict cardiovascular events, and respond to risk reduction therapies, including drugs, lifestyle changes, and dietary interventions. Recently, there have been several studies showing beneficial effects of tea on endothelial function, particularly endothelium-dependent vasodilation.
In a placebo-controlled crossover study, Duffy and colleagues showed that consumption of black tea (900 ml per day for four weeks) improved endothelium-dependent flow-mediated dilation of the brachial artery in patients with coronary artery disease [115]. Hodgson and colleagues showed a similar benefit of black tea consumption in patients with mildly elevated cholesterol levels [116]. Green tea has also been reported to improve brachial artery flow-mediated dilation [117,118] and circulating endothelial progenitor cells, which contribute to maintenance of vascular health [118]. One study suggested that green and black tea have equivalent effects on flow-mediated dilation in post-menopausal women [119]. Favorable effects on endothelial function have been reported with tea components, including EGCG [120]. In addition to improving FMD, green tea improves endothelium-dependent dilation of forearm microvessels in response to acetylcholine infusion in cigarette smokers and this improvement was associated with an increase in plasma nitric oxide [111]. On the other hand, tea consumption had no effect on carotid-femoral pulse wave velocity, a measure of arterial stiffness that depends in part on endothelial function [121].
Experimental studies have shed light on the mechanisms accounting for improved nitric oxide bioavailability following tea consumption. Initially investigators hypothesized that tea flavonoids might scavenge reactive oxygen species and prevent “inactivation” of nitric oxide, but as discussed above, there is little evidence that the plasma concentrations of tea flavonoids achieved following tea consumption are high enough to act via this mechanism. More recent studies indicate that tea extracts and individual tea polyphenols, including EGCG stimulate phosphorylation of endothelial nitric oxide synthase (eNOS) at serine 1177, a response that increases production of nitric oxide. The response occur via activation of the phosphatidylinositol 3-kinase (PI3 kinase)/Akt signaling pathway [122–124]. Subsequent studies suggest that this process also involves activation of p38 MAP kinase and transactivation of estrogen receptor alpha [125].
A number of other mechanisms contribute to the observed increase in eNOS activity following exposure of endothelial cells to tea components. For example, green tea polyphenols down regulate expression of caveolin-1 (Cav-1), an negative regulator of eNOS activity and this effect also involves activation of p38 MAP kinase [126]. Other polyphenol mixtures have been shown to activate AMP-kinase, a key regulator of cellular energy status, which also leads to activation of PI3K/Akt and eNOS phosphorylation [127].
Overall, there is a large body of working showing that tea consumption improves endothelium-dependent vasodilation in healthy human subjects and in patients with risk factors and established atherosclerosis. The effects are particularly strong following acute consumption of tea and occur despite acute effects of caffeinated tea to increase blood pressure. Many studies also show sustained improvements in endothelial function with longer-term tea consumption, while purified EGCG has an acute, but no chronic effect [120]. Experimental studies provide strong evidence that tea acts via specific signaling pathways in endothelial cells that are relevant to the pathogenesis of atherosclerosis. Given the strong links between endothelial dysfunction and the pathogenesis of atherosclerosis, a favorable effect of tea on the endothelium is a plausible mechanism that might account for reduced cardiovascular risk among individuals with higher tea consumption.
4.4. Anti-platelet effects
It is well established that clinical coronary syndromes such as unstable angina and acute myocardial infarction involve platelet aggregation and that anti-platelet agents such as aspirin and clopidogrel reduce cardiovascular risk [95]. A number of experimental studies suggest that tea has anti-platelet effects that might reduce cardiovascular risk. For example, Kang and colleagues reported that administration of EGCG or green tea extract to mice prolongs bleeding time, and prevents collagen-induced pulmonary thrombosis and death [128]. They also observed that EGCG inhibits agonist-induced aggregation of human platelets in vitro. The effects may be attributed to alterations in intracellular calcium signaling [129] and prostaglandin metabolism [130]. Theaflavins in black tea and green tea catechins have been shown to be potent inhibitors of platelet activating factor biosynthesis and platelet aggregation in a rabbit model [131]. It is important to note that the concentrations of EGCG and other tea components used in some of these in vitro studies (50 to 100 μM), greatly exceed the concentrations measurable in plasma following consumption of tea or EGCG supplement in humans [90,120].
In regard to human studies, Hodgson and colleagues observed that tea consumption by healthy volunteers reduced plasma levels of P-selectin, a marker of in vivo platelet aggregation, but ex vivo platelet aggregation was unaffected in that study [132]. Green tea consumption also lowered P-selectin levels in male smokers [112]. Steptoe and colleagues observed that black tea consumption for four weeks reduced platelet-leukocyte aggregates, an important measure of platelet activation that is relevant to coronary plaque rupture [110]. Duffy and colleagues also observed no effect of tea consumption on ex vivo platelet aggregation following consumption of black tea in patients with coronary artery disease [133], although that study may be limited by the background aspirin treatment in all of the study subjects.
In general, studies that examined ex vivo platelet aggregation failed to show beneficial effects, but measures of in vivo platelet activation appear to be improved following tea consumption. Experimental studies provide evidence of plausible mechanisms. Thus, the bulk of the available data support the hypothesis that platelet inhibitory effects might explain the observed relations between tea consumption and reduced cardiovascular risk.
4.5. Anti-proliferative effects
Another mechanism that might affect cardiovascular disease is the observed anti-proliferative and anti-migratory effects of tea components on vascular smooth muscle cells. EGCG arrests vascular smooth muscle cell proliferation in the G1 phase of the cell cycle and decreases the proliferative response following arterial injury in apolipoprotein E-null mice, a dyslipidemic model that is prone to develop atherosclerosis [134]. EGCG also inhibits vascular smooth muscle cell activation and proliferation by platelet-derived growth factor [135]. EGCG inhibits vascular smooth muscle cell migration through a reconstituted basement membrane barrier in an in vitro model that is relevant to atherogenesis [136]. Although there currently is no human evidence of such an effect, the anti-proliferative properties of EGCG have prompted investigators to consider developing EGCG-eluting polymeric stents for prevent of restenosis following angioplasty, a process that is primarily driven by vascular smooth muscle cell proliferation and migration [137].
5. Clinical Implications
The reviewed epidemiological studies and meta-analyses suggest that tea has protective effects against cardiovascular disease. In regard to the mechanisms that might account for such effects, there is evidence that tea might lower blood pressure and have favorable effects on blood lipids, glucose, and body weight. In addition, experimental studies and human intervention studies suggest that tea may have anti-inflammatory, anti-thrombotic, and anti-proliferative effects, and may improve the function of the vascular endothelium. Although tea polyphenols can scavenge reactive oxygen species and protect LDL against oxidation in vitro, human studies argue against an important in vivo anti-oxidant effect of tea. While the effects are modest compared to the effects of pharmacological interventions, in the opinion of the authors, the overall evidence suggests that tea consumption reduces cardiovascular risk by plausible mechanisms. The case for tea is strengthened by a similar body of work for protective effects of other polyphenol-containing foods and beverages such as grapes and red wine, cocoa, berries, and other fruits and vegetables [21,53,138–140]. The question is whether these findings translate to specific dietary recommendations for the general population and for patients with cardiovascular disease.
Making specific dietary recommendations about tea consumption as an approach to prevent or treat cardiovascular disease is problematic for several reasons. Importantly, there are no randomized clinical outcome trials with tea. Epidemiological studies of tea are unavoidably confounded by the lifestyles of tea drinkers and non-tea drinkers, background tea intake of the population, and many other factors. Most of the current management guidelines in the field of cardiovascular disease, particularly recommendations about drug treatment, are based on randomized clinical trials and meta-analyses of clinical trials that can control for such factors. There have been randomized studies of dietary approaches such as the Mediterranean diet to reduce cardiovascular risk, but none with tea. In drug studies, the control group can be randomized to a placebo and have zero intake of the studied factor. Tea, on the other hand, is a ubiquitous part of the diet and it is not possible or ethical to have a control group that consumes no tea over the three to five years needed to accumulate a sufficient number of cardiovascular events.
A number of other difficulties would make it extraordinarily difficult to conduct a randomized clinical trial with tea. It remains unclear what type and dose of tea to recommend or to study. Another barrier is the question of specific populations studied. Pharmaceutical studies focus on patients with cardiovascular disease, but the results are not expected to apply to the general population. Finally, there is the question of cost. Clinical outcome studies are extraordinarily expensive and unlike pharmaceutical studies, there is no sponsor with a profit motive to bear the cost of studying a whole food, such as tea.
Similar issues influence the utility of the available observational studies to guide dietary recommendations. The available epidemiological studies suggest favorable effects of green, oolong, and black tea and benefit from modest to only extremely high amounts of tea consumption. Smaller scale intervention studies looking at risk factors and mechanistic surrogate endpoints also examined a wide variety and types and doses of tea. Variable bioavailability due to differences in food matrix and human gut absorption further clouds the issue. Thus, it is remains extremely difficult to formulate dietary recommendations about how much and the type of tea to consume for the general population. Making recommendations for disease population is even more problematic.
Another important clinical implication of the reviewed studies is the potential use of tea extracts or individual tea components, such as EGCG, to promote cardiovascular health or prevent cardiovascular disease. Food, beverage and dietary supplement products designed to promote heart health are now a multi-billion dollar category in the U.S., with comparable markets in Europe, Japan and Australia. In regard to extracts, there is a lack of uniformity to the studied preparations, doses, and endpoints that make it hard to make specific recommendations and as for whole tea, there are no randomized outcome studies. For purified components, such as EGCG, there is a large body of evidence for favorable effects, but studies suggest that the benefits are limited to short-term acute effects reflective of the short plasma half-life of one to two hours [120]. To be beneficial, some type of slow-release preparation would be needed to provide a sustained increase in blood levels. Consideration of such preparations likely crosses the line from dietary supplements to drugs, with the attendant regulatory issues.
In 2006, Ito En, Ltd., a manufacturer of green tea and green tea products filed a petition to the U.S. Food and Drug Administration (FDA) to make a qualified health claim for green tea and green tea extracts based on studies showing favorable effects on cardiovascular disease risk factors [141]. The FDA reviewed observational studies that examined the relationship between green tea and cardiovascular disease endpoints, including many of the studies discussed in this review. They also considered intervention studies that examined the effects of green tea on blood pressure and blood cholesterol as surrogate endpoints for cardiovascular disease. Although they considered many observational studies, they argued that intervention studies provide the most scientifically valid information. For this reason, they particularly focused on four intervention studies that failed to show a benefit of green tea on blood pressure [34] and lipids [51,87,142] and three intervention studies that failed to show an effect of green tea extract on cholesterol [51,93,143]. On the basis of these studies, they concluded that there was no credible evidence to support a relationship between consumption of green tea and reduced risk of cardiovascular disease. They cited the data for vitamin E and folate as examples of other dietary supplements that showed strong associations in observational studies, but no benefit in randomized trials, further justifying their decision to discount many of the observational studies suggesting favorable effects. While they did not find that green tea was unhealthy, the decided that the available evidence did not support a qualified health claim for a benefit against cardiovascular disease. continues a partial list of randomized intervention studies examining effects of tea on risk factors that have been published since the FDA ruling in 2006. Many of these studies show benefit, raising the possibility that the question of a qualified health claim for tea might be reconsidered.
Table 2
Intervention studies of tea on blood pressure and lipids since the FDA decision in 2006
First author [reference] | Endpoint | Study design | Result |
---|---|---|---|
Nagao [36] | Body fat, LDL, blood pressure | Green tea extract, randomized parallel group, 12 weeks, n=240 | Benefit |
Bertigaglia de Santana [48] | LDL, HDL, triglycerides | Green tea, randomized parallel group, 90 days, n=25 per group | No benefit |
Fujita [47] | LDL, triglycerides, body weight | Black tea, randomized parallel group, 3 months, n=47 | Benefit |
Brown [37] | Blood pressure, LDL, HDL, | EGCG, randomized parallel group, 8 weeks, n=88 | Benefit on blood pressure, no benefit for lipids |
Nantz [38] | Blood pressure, LDL | Tea extract, randomized parallel group, 3 weeks, n=111 | Benefit on LDL and blood pressure |
Basu [49] | Blood pressure, LDL, body weight | Green tea extract, randomized parallel group, 8 weeks, n=35 | Benefit on body weight, no benefit on LDL |
Trautwein [50] | Serum lipids | Black tea extract, randomized parallel group, 11 weeks, n=102 | No benefit |
Hooper [53] | LDL | Meta-analysis of 133 green tea intervention studies | Benefit on LDL |
At this time, however, manufacturers cannot make claims about benefits against cardiovascular disease in advertising and labels for green tea or black tea. Advertising claims are different from guidelines and recommendations from non-commercial entities, such as the American Heart Association (AHA). In the most recent dietary guidelines, the Nutrition Committee of the AHA recommended that individuals consume a diet rich in fruits and vegetables to reduce the risk for cardiovascular disease [144]. Such a diet includes green and black tea.
6. Conclusion
In this article, we have reviewed a representative portion of the extensive published literature on tea and its role in cardiovascular disease prevention. Some, but not all observational studies suggest a reduction in cardiovascular disease. There also are mixed data about the effects of tea on risk factors from observational and intervention studies. Mechanistic studies in experimental models and human subjects have identified a number of plausible mechanisms of benefit, including anti-inflammatory and anti-platelet effects as well as favorable effects on the vascular endothelium. No randomized trials have examined the effects of tea on cardiovascular events, and there are many barriers to the conduct of such a trial. Thus, no definite conclusion can be drawn from the current data and no specific dietary recommendations can be made about whether tea promotes reduces risk for cardiovascular disease. Furthermore, the available literature does not provide a clear answer about the type and/or amount of tea that should be consumed as part of a heart healthy diet.
At the present time, it is clear that tea is a popular, economical and safe drink which is enjoyed daily by millions of people all across the world. Given the high consumption and distribution of tea worldwide and the potential health effects of tea, further study is justified. In the meantime, freshly brewed green or black tea appears to be a reasonable dietary choice to consider as part of lifestyle and dietary approach to prevent heart disease.
Acknowledgments
Dr. Vita previously received research grant support from the North America Tea Trade Health Research Association, Unilever, Inc., Welch’s, Inc., USANA Health Sciences, Inc. He has current research grants from DSM Nutritional Products, Ocean Spray, Inc., The Almond Board of California. He has received consultation fee or speaker honoraria from Unilever, USANA, DSM, Ocean Spray, and the Almond Board of California. He also is supported by research grants from the National Institutes of Health ({“type”:”entrez-nucleotide”,”attrs”:{“text”:”HL083801″,”term_id”:”1051654209″,”term_text”:”HL083801″}}HL083801, {“type”:”entrez-nucleotide”,”attrs”:{“text”:”HL081587″,”term_id”:”1051651995″,”term_text”:”HL081587″}}HL081587, {“type”:”entrez-nucleotide”,”attrs”:{“text”:”HL083269″,”term_id”:”1051653677″,”term_text”:”HL083269″}}HL083269, and HL75795 and {“type”:”entrez-nucleotide”,”attrs”:{“text”:”HL102299″,”term_id”:”1051673608″,”term_text”:”HL102299″}}HL102299).
Footnotes
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What Type Of Tea Is Good For Heart Disease Prevention?
Drinking tea has a lot of benefits to one’s health. It is proved
that having quite a few cups of tea daily can help lower blood cholesterol
levels. It can lessen the damage caused by smoking and might also prevent
cancer and heart disease.
According to studies, tea is good for preventing heart disease,
probably due to the polyphenols, which are basically antioxidants. These
polyphenols help in clearing up harmful radicals in the body. However, the main
reason is still not known.
Drinking tea helps to reduce the risk of coronary artery disease
and other cardiovascular issues such as strokes, heart attacks, angina, and
cardiac arrest. A study was conducted to examine coronary artery calcium
scores. The results showed that people who drank two to three cups of tea daily
had better coronary calcium scores compared to those who never drank tea. It
was also noted that regular drinkers had low chances of heart incidents than
those who never drank tea.
Types of teas that help the heart
The type of tea we drink does matter, just like any medicine,
when it comes to health benefits. It is important to consider your caffeine
sensitivity before choosing any type of tea for health purposes. Usually, the
best types of teas are made from the Camellia sinensis shrubs such as black,
white, green, and Oolong tea.
Black Tea
Black tea is highly oxidized, which is why it is black in color.
Most doctors advise coffee-drinking heart patients to switch to black tea since
it has half the amount of caffeine in the same quantity of coffee. Research
showed that people who had three cups of black tea daily had lower triglyceride
levels and improvement in their cholesterol levels.
However, black tea has caffeine and might not prove to be a good
choice for people with very high blood pressure or a fast heart rate. Also, it
may decrease the clotting of blood, which makes it unsafe for those taking
blood-thinning drugs.
Green Tea
Green tea is prepared by harvesting the leaves, leaving them to
wither, and then steaming them, which means there is no oxidation. Heart
specialists suggest drinking green tea as much as you can if you are a regular
tea drinker. However, it is advised not to take in with sugar, or it might lose
its good effects.
Green tea is proved to lower LDL cholesterol levels and
triglycerides, which means it is good for the heart. Green tea is very
beneficial for heart health as it reduces the risk of heart disease and death
from heart stroke or attack.
Green tea also contains very powerful antioxidants that help
prevent atherosclerosis, the accumulation of plaque in the arteries. It also
boosts one’s metabolism, which eventually makes it easier to maintain a healthy
weight. Moreover, the tea also improves the function of specific cells in the
bloodstream.
White Tea
White tea is a type of tea that comes from the young buds of the
tea plant and is processed very briefly. Most specialists suggest that it is
the purest tea and is good for heart health. The flavonoids present in white
tea help dilate the arteries, which ultimately lowers blood pressure, reduces
cholesterol, and even prevents blood clotting. The tea is not only good for the
heart but also the whole circulatory system.
Oolong Tea
Oolong Tea is made by heating crushed and oxidized tea leaves.
It is known to help patients with coronary heart disease by lowering blood
cholesterol levels. Also, it reduces triglycerides and food intake. However, if
one is planning on taking Oolong tea, he must consult his heart
specialist.
Chamomile Tea
Chamomile tea is an herbal tea, which means it does not really
come from a tea plant. However, it still has a number of benefits for health.
It has an indirect benefit for cardiac health that is sleep. Most heart
patients have issues like they are don’t get enough sleep. Sleep is very
significant for every human being. Chamomile tea helps soothe the body and
makes it easy for one to have a peaceful night’s sleep.
Ginseng Tea
Ginseng tea is a natural blood thinner and is known to boost
heart health. It relaxes the arteries, therefore, lowering blood pressure. This
type of tea functions as a blood thinner as it blocks platelet adhesion.
Furthermore, tea also improves cholesterol levels.
Ginseng tea is a tasty substitute for a sweet beverage and also
has a lot of benefits to boost heart activity. The tea not only works as a
slimming agent but also reduces the intake of excess sugar that is harmful to
the heart.
Final Verdict
Considering all the above teas and their benefits, green tea is
the best type of tea for preventing heart disease. It is a light and aromatic
tea which significantly lowers LDL cholesterol and triglycerides. These
elements are responsible for death from a stroke or heart disease.
Studies have shown many possible links between green tea and
heart disease. People who drank up to five cups of green tea daily had a 26%
lower chance of death from a stroke than people who drank little or no cup of
tea. In addition to this, people who had more green tea had a lower risk of
coronary heart disease than people who did not.
Green tea has a potential relationship with the benefits
provided to the heart. However, there are quite a few side effects of this tea.
It is reported that it can raise liver enzymes and is also a major source of
oxalate, which might lead to kidney stones. Hence, it can be said that drinking
more than 6 cups of green tea will have more risks than benefits. So, if
consumed sensibly, it can greatly improve one’s heart health.
At South Florida Cardiovascular Specialist, our experts will
provide you with the best treatment and advice. You can consult us to get help
with heart disease prevention so that you get to live a happy and healthy
lifestyle.
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What Happens to Your Heart When You Drink Tea
If you want to learn all about how drinking tea can impact your heart, you’d better put the kettle on. There are dozens of studies suggesting that lowering your risk of heart disease may be as flavorful as sampling a wide variety of black, green, white, and even herbal teas.
Let this one steep a bit: A large observational study in the European Journal of Preventive Cardiology analyzed health and behavioral information from 100,000 Chinese people for more than seven years. The 2020 report found that habitual tea drinkers who drank more than three cups of tea a week had a 20% lower risk of heart attack and a 22% lower risk for dying of heart disease when compared with people who drank fewer than three cups weekly.
Another study of more than 40,000 Japanese adults in the Journal of the American Medical Association saw a 26% lower risk of death from a heart attack or stroke in people who drank more than five cups of green tea a day. (Related: What Happens To Your Body When You Drink Green Tea.)
How is tea so good for your heart?
To understand why drinking tea may be so good for your heart, we need to look at how your blood pressure affects your heart health. High blood pressure, called hypertension, damages the walls of your arteries making them stiff and possibly leading to blockages.
The higher your blood pressure readings, the more risk you have for cardiovascular disease (CVD), heart disease, and stroke. When your blood vessels aren’t as elastic as they should be, the flow of blood and oxygen to and from your heart decreases, leading to chest pain, and possibly heart attack or heart failure. (If high blood pressure runs in your family, be sure to read about these Foods Proven to Lead to High Blood Pressure.)
“Research is showing that high tea consumption leads to a healthier heart and reduced risk of disease,” says nutritionist Lisa Richards, CNC, creator of the Candida Diet. “This is because teas contain beneficial plant compounds known as polyphenols that act as antioxidants in the body.”
Tea and its metabolites like polyphenols play a role in relaxing arteries by reducing inflammation and enhancing the activity of nitric oxide in the endothelium, the layer of cells lining the inside of blood vessels. Nitric oxide is a vasodilator that causes the endothelium to relax, widening blood vessels and improving blood flow, according to a study in Nutrients.
Tea’s key compound is EGCG.
Tea may also significantly lower the risk of heart disease and stroke by reducing low-density lipoprotein (LDL), the “bad” cholesterol that can build up in arteries and form plaques.
“Green tea is full of polyphenols and catechins, two antioxidant compounds recognized for their anti-inflammatory properties,” says culinary and tea expert Kristen Lorenz at The Spice & Tea Exchange.
“Green tea is a particularly rich source of a potent form of catechin called epigallocatechin gallate, or EGCG, that’s been shown to ‘turn off’ the genes that trigger obesity, diabetes and the storage of belly fat,” according to Kelly Choi, author of our Eat This, Not That! book, The 7-Day Flat-Belly Tea Cleanse.
Gimmie a tea for triglycerides!
According to Nutrition Journal, green tea has also been shown to improve cholesterol levels. But if you prefer the taste of black tea to green, don’t worry.
“Black tea has been found to both lower triglycerides, a dangerous blood fat, and raise HDL (good) cholesterol because of the polyphenols found within this tea,” says Richards. “These compounds give teas their bright colors, which means herbal teas provide a host of polyphenols resulting in similar benefits as well.”
For more tips for your ticker, read Simple Ways to Keep Your Heart Healthy.
Green Tea Benefits | Tea for Heart Health
- According to a new study published in the European Journal of Preventive Cardiology, tea could help reduce your risk of heart disease and stroke.
- Researchers found that drinking tea—especially green tea—three or more times a week can significantly improve your overall heart health due to a type of antioxidant.
While coffee tends to get all the love—especially among athletes—tea drinkers know their favorite way to caffeinate and warm up packs a ton of health benefits, too. Not only can it help boost your brain function, but according to new research out of China, it can also help protect your heart.
In the study, published in the European Journal of Preventive Cardiology, researchers looked at the data of over 100,000 participants in the China-PAR project—which aimed to predict risk factors of atherosclerotic cardiovascular disease—who had no history of heart attack, stroke, or cancer. The participants were split into two groups: those who drank tea three or more times per week and those who drank tea less than three times per week.
After a follow-up period of an average of seven years, researchers found that those who drank tea regularly had better heart health compared to those who didn’t. Specifically, they were 20 percent less likely to suffer from heart disease or stroke, 22 percent less likely to die of heart disease or stroke, and 15 percent less likely to die from other health issues.
After the initial follow-up period, researchers checked back with participants five years later, and found that the connection between tea and heart health was even stronger: Regular tea drinkers were now 39 percent less likely to suffer from heart disease or stroke, 56 percent less likely to die from heart disease or stroke, and 29 percent less likely to die from other health issues.
So why is tea so good for your ticker? According to lead study author Xinyan Wang, Ph.D.(c), of the department of epidemiology at the Chinese Academy of Medical Sciences and Peking Union Medical College, tea is a rich source polyphenols. Polyphenols, he told Runner’s World, are an antioxidant that has been shown to relieve inflammation and improve cell function in the heart and blood vessels. This, in turn, can prevent against heart disease and stroke.
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While green tea contains more polyphenols than other types of tea, people can still reap the benefits from other types, such as black tea.
“Similar protective effects against cardiovascular disease and all-cause mortality were also observed for scented tea and black tea in the current study,” Wang said.
Although the results for other types of tea weren’t as significant as green tea, this could be because a majority of the study’s participants likely drank green tea more regularly since it’s common in Asia, according to Wang.
“By contrast, black tea is popular in European countries, and was found to be associated with reduced risks of stroke and coronary artery disease in the Netherlands, Finland, and Sweden,” he said.
Keep in mind, adding milk or sugar to your tea could lessen tea’s advantages. A 2007 study in the European Heart Journal found that milk counteracted the health benefits of tea on blood vessel function. Plus, consuming too much sugar per day could lead to poor heart health as well, according to the American Heart Association.
[Stay injury free on the road by getting on the mat with Yoga for Runners.]
It’s also worth noting that while the heart-healthy benefits of tea were more pronounced in men in Wang’s study, there are two possible reasons for why that could be: First, men consumed about 2.5 times more tea in their daily lives than women did. Second, women usually have a lower incidence and mortality of atherosclerotic cardiovascular disease in China and East Asian countries to begin with.
“Investigations of the China-PAR project are still ongoing, and with larger total person-years of followup among women, the results will become more pronounced and reliable in the further studies,” Wang said.
The bottom line? Adding tea into your diet—whether you use it to get you going in the morning or help you wind down at night—can keep your heart healthy enough to run and live your best.
Danielle Zickl
Health and Fitness Editor
Danielle specializes in interpreting and reporting the latest health research and also writes and edits in-depth service pieces about fitness, training, and nutrition.
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The 10 Best Teas For Health Backed By Science – Sencha Tea Bar
Tea is a healthy beverage that can help soothe everything from pain and inflammation to a scratchy throat. Most of us reach for a cup of tea when we’re feeling under the weather or want to warm up on a cold winter’s day. But tea can also be consumed on a daily basis to help improve overall health.
Here, we’ve compiled a list of the best teas for health. From rich and earthy to airy and floral, you’ll find a flavor you love to go with the health benefits. Want to get your hands on healthy teas today? Check out our collection of the best teas for health right here.
The 10 Best Teas To Drink For Health
1. True Teas (Green, White, Oolong, Black, and Pu-erh Teas)
True teas are made from the leaves of the Camellia sinensis plant, also known as the tea plant. All other teas are made from leaves, roots, and flowers of different plants—those teas are called herbal teas. True teas have been consumed for centuries and their origins can be traced back to China thousands of years ago. They’re backed by the most scientific research and are renowned for a wide range of health benefits.
Green Tea
Green tea is considered one of the healthiest teas available. It’s typically modestly processed and features delicate leaves that are either steamed or roasted. The flavor is earthy and grassy with notes of seaweed.
Green tea is packed with antioxidants and catechins including one particularly well-researched one called EGCG or epigallocatechin gallate. Research shows this tea catechin may help to protect heart health by decreasing inflammation and improving blood circulation (1). By improving circulation, drinking green tea helps to lower the risk of heart disease including heart attacks. The anti-inflammatory properties of the tea help to lower blood pressure and reduce LDL cholesterol.
Green tea may also help to accelerate weight loss by boosting metabolism and encouraging the breakdown of fats—rather than glucose—into energy (2). Studies have also shown that green tea may be able to prevent the replication of certain types of cancerous cells including those found in breast cancer and lung cancer. In some conditions, green tea may even be able to induce apoptosis of the cancer cells themselves. (3).
White Tea
White tea is the least processed of the true teas. It’s tea leaves maintain a natural green hue as the leaves are simply sun-dried after harvesting. It has less caffeine content compared to other true teas so you can drink it all day long. White tea also offers a delicate flavor that is slightly floral and nuanced.
Drinking white tea may help to prevent the onset of type 2 diabetes. One study found that drinking four or more cups of white tea per day may lower your risk of developing type 2 diabetes. The antioxidants in the tea work to decrease insulin resistance and can regulate blood sugar levels (4).
Oolong Tea
Oolong tea is a semi-fermented tea. The tea leaves are harvested, withered and then oxidized anywhere from 8 to 80 percent. The different oxidation levels result in a flavor profile that ranges from airy and sweet to robust and earthy.
Oolong tea contains theasinensins—chemical compounds that are responsible for a range of health benefits. Research shows these compounds boast antioxidant activity, decrease inflammation, have anti-cancer protective effects, and antimicrobial properties (5).
Black Tea
Black tea, like green tea, is known for powerful health properties and has been extensively researched. It has the highest caffeine content of all the true teas and can be a great replacement for a cup of coffee. It also contains an amino acid known as L-theanine, which helps to slow the absorption of caffeine and produces a longer-lasting kick of energy—without the jitters.
Research shows that drinking three or more cups of black tea daily can reduce the risk of coronary heart disease (6). For Americans who are prone to heart disease, drinking tea is one easy way to improve health with very few side effects. Black tea contains polyphenols that help to streamline digestion and alleviate problems. One study found that these polyphenols help to promote the growth of good gut bacteria with inhibiting pathogens that can make you sick (7).
Pu-Erh Tea
Pu-erh tea is one of the more unique types of tea. It is an aged tea that offers rich flavor and can be aged for more than 50 years. There are two types of pu-erh teas: raw pu-erh and ripe pu-erh. Raw pu-erh undergoes a natural fermentation process while ripe pu-erh tea is aged using wet cloths that encourage microbial oxidation. This tea offers robust flavor with notes of floral and sweet flavors paired with roasted, woodsy notes.
Pu-erh tea contains antioxidants that help to eliminate free radicals, detoxify the body, and prevent oxidative stress. Oxidative stress has been linked to a host of ailments from premature aging to mental decline and even the onset of Alzheimer’s disease (8).
2. Rooibos Tea
Rooibos tea is a South African drink made from the leaves of the red bush plant. This plant only grows in the Cederberg Mountains of Western South Africa. When infused in hot water, the leaves brew into a vibrant red hue with tart notes. It’s a refreshing beverage both hot and cold and offers health benefits backed by research.
Research shows that rooibos tea contains antioxidants that boost overall health and may protect the liver. One study demonstrated that rooibos tea decreased oxidative stress and boosted liver function (9). Additional preliminary research shows that rooibos tea may have cancer prevention effects and can improve digestion (10).
3. Hibiscus Tea
Hibiscus tea is a delicious floral tea made from the calyxes of the plant. It brews into a magenta hue with a flavor similar to cranberries. It is the perfect blend of tart and sweet and offers medicinal benefits that have been enjoyed by indigenous societies for centuries.
Studies show that hibiscus tea demonstrates antitumoral properties. One such study published in the Brazilian Journal of Biology found that phenolic compounds and flavonoids helped to eliminate free radicals and prevent tumor growths (11). These properties may help to also prevent aging by protecting cells.
Hibiscus tea also boasts heart health benefits thanks to anti-inflammatory and antioxidant properties. One meta-analysis found that hibiscus tea significantly decreases systolic and diastolic blood pressure (12).
4. Ginger Tea
Ginger tea is made from the root of the ginger plant. It offers a spicy flavor that invigorates taste buds and pairs well with lemon and honey.
Ginger tea is an excellent beverage when it comes to digestive health. Ginger has widely been regarded as an aid for nausea caused by morning sickness and motion sickness. In fact, ginger can be found in gum and natural supplements used to treat nausea.
Ginger tea helps to decrease inflammation in the stomach and intestines, helping the body process food more efficiently. The decrease in inflammation can also soothe muscles that cause stomach cramps. Research shows that ginger tea may also inhibit serotonin receptors, thus decreasing nausea and stress (13).
5. Peppermint Tea
Peppermint tea is another excellent digestive tea. This tea is made from the leaves of dozens of peppermint plants including Nana mint and chocolate mint. Peppermint tea offers a refreshing flavor with a tingling sensation. The aroma is invigorating and the tea brews into a pale green hue.
Peppermint tea, like ginger tea, has long been used as a digestive aid. The menthol in peppermint tea helps to decrease inflammation and settle an upset stomach. The tea also boasts analgesic effects as it helps to reduce inflammation and pain. The main agents in peppermint tea’s health benefits are phenolic compounds such as rosmarinic acid and flavonoids (14).
6. Chamomile Tea
Chamomile tea is a beloved bedtime tea known for its calming effects. This tea boasts a delicate flavor that is reminiscent of crisp green apples. It’s refreshing and soothing at the same time.
The most prominent health benefit of chamomile tea is its ability to increase relaxation and improve sleep. One study showed that chamomile tea significantly reduced depression scores while increasing the time spent in deep sleep cycles (15). A second study found that chamomile tea reduced the number of times patients woke up during the night and improved their alertness the following day (16).
Toast To Your Health With Tea
Tea is packed with antioxidants, polyphenols, catechins, and other healthy compounds that boost overall health. Drinking tea may help to lower cholesterol, boost energy, and support immune health. The health benefits of tea also include easier weight management and it can also help you unwind and de-stress.
Boost your tea consumption and toast to your health. Choose from sweet, vegetal Japanese green teas or opt for robust flavor with European or Chinese black teas. Mix it up and try different types of tea to find what suits your taste buds. The best tea for your health is the one you’ll actually drink. Choose a delicious tasting tea and enjoy a cup or two per day to reap the benefits of this healthy beverage.
Sources:
1. https://www.ncbi.nlm.nih.gov/pubmed/17906191
2. https://www.ncbi.nlm.nih.gov/pubmed/12873714
3. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3509513/
4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2669862/
5. https://www.sciencedirect.com/science/article/pii/S2213453015000555
6. https://www.ncbi.nlm.nih.gov/pubmed/16855537
7. https://www.tandfonline.com/doi/full/10.1080/87559129.2010.535233
8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4840676/
9. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3967803/
10. https://www.uofmhealth.org/health-library/hn-3938007
11. https://www.ncbi.nlm.nih.gov/pubmed/25945622
12. https://www.ncbi.nlm.nih.gov/pubmed/25875025
13. https://www.ncbi.nlm.nih.gov/books/NBK92775/
14. https://www.ncbi.nlm.nih.gov/pubmed/16767798
15. https://www.ncbi.nlm.nih.gov/pubmed/26483209
16. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3198755/
Coffee and Green Tea May Reduce Death Risk After Stroke or Heart Attack
Key Takeaways
- Studies have previously linked drinking green tea and coffee to reduced mortality risk in the general population.
- According to a new study, drinking these beverages may reduce mortality for stroke and heart attack survivors as well.
- Maintaining an overall healthy lifestyle is likely more effective at reducing mortality risk than incorporating green tea or coffee into your day-to-day.
Regular green tea and coffee consumption have previously been found to offer a myriad of health benefits, ranging from reducing the risk of cardiovascular disease to improving brain function. But now researchers suggest that the beverages can also reduce the risk of death for those who have experienced a stroke or heart attack.
Daily green tea consumption lowered stroke survivors’ death risk by 62%, and daily coffee consumption lowered heart attack survivors’ death rate by 22%, according to the study. The study’s findings were published in February in the journal Stroke.
“This study is an interesting large cohort study that finds that green tea and coffee consumption may have an association with mortality,” Barry Silverman, MD, an Atlanta-based cardiologist not involved in the study, tells Verywell.
The Findings
To conduct this study, researchers evaluated over 46,000 participants from 45 communities across Japan. After classifying participants into one of three groups—history of stroke, history of myocardial infarction (heart attack), or no history of stroke or heart attack—the researchers then examined the amount and frequency of green tea and coffee intake and evaluated any correlation in outcomes.
After data was analyzed, researchers found that stroke survivors who drank at least seven cups of green tea every day lowered their mortality risk by 62% when compared with those who did not drink tea consistently.
Heart attack survivors who had one cup of coffee every day lowered mortality risk by 22% when compared with those who did not have a daily cup of coffee. Subjects who did not have a history of stroke or heart attack and drank one or more cups of coffee a week had a 14% lower risk of overall mortality compared to non-coffee drinkers.
“I am not surprised by this study’s findings, primarily because we know that green tea has excellent benefits on two important components of cardiovascular health: reducing inflammation and improving blood vessel function,” Michelle Routhenstein, MS, RD, CDE, CDN cardiology dietitian and owner of Entirely Nourished, tells Verywell. “Many previous studies focused on high volumes of green tea consumption, whereas this study focused on the dose-response as well, confirming that any dose of green tea is still beneficial for heart health.”
While Silverman agrees that tea and coffee are likely not harmful to consume after a stroke or a heart attack, he is not convinced that it is necessarily helpful based on the current study.
“The study notes there is significant variation in diabetes, intake of fruits and vegetables, educational level, mental stress, and other factors, in addition, no physiologic mechanisms that is suggested for the benefit from the consumption,” Silverman says. “Drinking tea in Asian society and coffee in Western society is almost ubiquitous and may reflect as much on the personality, lifestyle, and character of the individual all of which are hard to define in a scientific study and which we understand may have a significant effect on cardiovascular morbidity and mortality.”
He says that the only generalization he can make is that green tea and coffee consumption do not appear to be harmful. “The mega numbers of the study I feel exclude harm, but there are too many other variables to prove the tea and coffee lower mortality,” he says.
What This Means For You
If you are a survivor of a stroke or heart attack, drinking coffee or green tea may help reduce your risk of death. But more research is needed before researchers can make a definite recommendation. Overall, maintaining a healthy lifestyle with regular exercise and healthy eating helps reduce your risk of death and disease.
Tea, Coffee, and Mortality
This is the first study to highlight the effects of coffee and tea on mortality outcomes for people who have experienced a stroke or heart attack. Previously, data has only been available on coffee and tea consumption’s effect on individuals without preexisting conditions.
In one study, also conducted on Japanese participants, over 300,000 people were evaluated on their green tea consumption frequency and mortality outcomes. Results showed when compared with individuals who consumed less than one cup of green tea per day, those who drank more than 5 cups per day had a decreased risk of overall mortality—especially for heart and cerebrovascular disease.
And in a meta-analysis evaluating 40 studies, coffee consumption appears to reduce all-cause mortality risk, when participants consumed a minimum of 3.5 cups of coffee a day.
Reducing Mortality Risk
According to the current data, drinking green tea and coffee may help reduce mortality risk in all people, including those who experienced a stroke or heart attack. But some key factors need to be kept in mind about the way these beverages are typically served in Japan, according to Hiroyasu Iso, MD, a professor of public health at Osaka University in Japan, and the study’s corresponding author:
- Green tea is often prepared with water and no added sugar
- Coffee is often served black, or with a small amount of sugar and milk
So, to reap the potential benefits, downing a double-mocha Frappuccino or a green tea latte loaded with sugar is not the best move. Pure green tea or coffee is your best bet.
If you enjoy coffee or tea, including it into an otherwise healthy diet will likely not cause any harm, and may do some good. Routhenstein suggests those who enjoy their green tea add a squeeze of lemon to their cup to “bump up the antioxidant content even further.”
If you experienced a heart attack or stroke, avoiding smoking, regular exercise, and healthy eating appear to help reduce the risk of death. Green tea and coffee can certainly be a part of that healthy routine. But until we have more data focused on green tea and coffee’s effect on mortality for stroke and heart attack survivors, don’t force yourself to down those drinks just yet if you’re not a coffee or tea lover.
90,000 Is tea good for the heart? | PHARMACY Weekly
According to a study by scientists from the American Heart Association, drinking just 1 cup of tea daily can be beneficial for heart health. For example, a study showed that individuals who drank a cup of tea daily had a 35% lower likelihood of developing myocardial infarction or other cardiovascular events compared with those who did not drink it. The study also showed that tea drinkers were less likely to have signs of atherosclerosis of the blood vessels than those who did not drink the tea.In turn, the deposition of calcium on the walls of blood vessels has been associated with diseases such as cardiovascular disease and stroke.
This study involved more than 6 thousand men and women without a history of cardiovascular disease. For 11 years, scientists monitored volunteers to analyze which of them had suffered a heart attack, stroke, chest pain, or died of cardiovascular disease during this period. The researchers also assessed the level of calcification of the blood vessels of the participants over 5 years by comparing the results of computed tomography at the beginning of the study and after a certain time.
Study results demonstrated that individuals who drank a cup of tea (black or green) per day had a 1 / 3 lower risk of developing heart disease and cardiovascular events during the study period than those who did not drink tea. In turn, participants who drank 1-3 cups of tea a day experienced a decrease in blood vessel calcification.
According to scientists, in moderate tea drinkers, the progression of arterial calcification was slowed down along with a decrease in the incidence of cardiovascular diseases.The reasons for this association have not been studied in detail. However, the results of this study have something in common with those of previous studies, which showed that the flavonoids found in tea can have a positive effect on the cardiovascular system. In turn, other studies have focused on the antioxidant properties of tea components. Thus, scientists emphasize that it is too early to say that drinking tea will help reduce the risk of myocardial infarction and stroke, as more research is needed in this area, but the available data indicate a positive effect of tea components on the cardiovascular system.
Based on materials from www.medicinenet.com
90,000 Tea and coffee protect the heart from disease
Photo caption,
Coffee and tea are beneficial, but a healthy lifestyle is more important, scientists say
Drinking several cups of tea and coffee a day can be prevented the development of heart disease, according to a study conducted by Dutch scientists.
Experts base their conclusions on data received from 40 thousand.people, their observations continued for 13 years.
According to the study, people who drink more than six cups of tea a day reduce their risk of heart disease by a third. Two to four cups of coffee will yield similar results: the risk of illness is reduced by 20%.
At the same time, the scientists emphasize that in the case of consuming significantly more coffee, the therapeutic effect disappears. But they add that large doses of the drink do not in any way increase the risk of premature death from any disease, including cancer and stroke.
Experts say that the most beneficial compounds found in tea are polyphenol antioxidants. According to some reports, adding milk to tea negates their positive effect, but some scientists do not confirm this information.
Anyway, in Holland it is customary to drink coffee with a little milk, and tea – without it at all.
Healthy lifestyle
It has been found that coffee contains compounds that can both reduce and increase health risks: on the one hand, coffee can raise cholesterol levels, on the other hand, it helps to eliminate inflammatory processes associated with heart disease.
“The results of the study will delight tea and coffee lovers,” says one of the authors of the work, Professor Yvonne van der Schouve. “These drinks seem to be good for the heart and do not increase the risk of death from other diseases.”
Representatives of the British charity British Heart Foundation welcomed the results of the work of the Dutch scientists.
“This study provides further evidence that moderate doses of tea and coffee do not harm most people, and may even reduce the risk of heart disease and death,” says Ellen Mason of the British Heart Foundation.
“However, it is worth remembering that the most important thing for maintaining good heart function is a healthy lifestyle,” the expert continues. “For example, a cigarette accompanying a cup of coffee negates all the benefits. without any physical exertion – it is unlikely that it will bring any benefit to your heart. ”
Strengthens the heart, relieves abdominal pain and 3 more benefits of chamomile tea
Chamomile flower tea for those who care about their health.
Photo: pixabay.com
Chamomile tea has many beneficial properties, from fighting insomnia to normalizing blood sugar levels.
Many people know that herbal teas have medicinal properties. But when it comes to chamomile, many people doubt it. But in vain: chamomile tea is healthy and is a great option for a decaffeinated drink.
The five most famous benefits of chamomile tea for adults:
Relieves stress. Anxiety is a real scourge of modern society. Chamomile tea helps with anxiety symptoms, acts as a sedative in stress. In this case, you can brew chamomile or use it in capsule form.
Fights insomnia. This is an excellent sleep stimulant. It acts on receptors in the brain that help sleep. The study found that those who drank chamomile tea every night for two weeks improved their sleep quality.
Helps with abdominal pain. A cup of chamomile tea may relieve upset stomach, menstrual cramps, irritable bowel syndrome, upset stomach and bloating.
Strengthens the heart. Antioxidants such as flavones can help reduce the risk of heart disease. Thanks to these properties, chamomile tea maintains a healthy level of blood pressure, makes blood vessels and arteries more elastic.
Normalizes Blood Sugar Levels: Chamomile helps lower blood sugar levels, which will benefit people with diabetes. The study found that those who drank chamomile tea for two months had significantly lower average blood sugar levels compared to those who drank only water.
Earlier, “Kubanskie Novosti” talked about drinks that will save you from insomnia.
90,000 Preventive measures for the health of the heart and blood vessels in children
The key to the well-coordinated work of the circulatory system is the early prevention of heart disease in children and adolescents. Such measures can be taken from the very birth of the child.
The World Health Organization has identified four measures for the prevention of cardiovascular pathologies in patients of all ages, including children.The same recommendations were supported by the Russian Society of Cardiology. These measures include:
- getting rid of bad habits;
- proper nutrition;
- weight normalization;
- physical activity.
Rational nutrition
Thanks to nutrition, a normal level of blood pressure is maintained, an active lipid metabolism occurs – split fats are excreted from the body, and not deposited on the walls of blood vessels.
The risk of improper fat metabolism occurs in the first year of life, at 5-6 years of age, during puberty. The first critical period is associated with the transition from breast milk to artificial feeding – often parents make the wrong diet, devoting most of it to fat rather than protein.
For parents, after transferring to artificial feeding, it is very important to observe the following rules for feeding a child:
- moderation – food should provide a waste of energy per day, but no more.In children, metabolism occurs one and a half times faster than in adult patients. With increased nutrition, but less energy consumption, food is deposited in fat and provokes excess body weight in a child;
- Diversity – The child should receive a variety of foods. This is not only protein food, but also fruits, vegetables, healthy drinks. It is important to correctly combine the ratio of BJU in the child’s nutrition;
- rationality – any food should be nutritional or energy value for the baby.
The child needs the following nutrients:
- meat products (all types of lean poultry, pork, beef) – the daily requirement of a one-year-old child is 80 g, and after a year it is calculated 4 g per 1 kg of weight;
- seafood, fish – the dosage of this category of products is calculated in the same way as for meat;
- milk and fermented milk products – 200-250 g;
- vegetables – 200 g;
- fruits – 150 g;
- eggs – 2-3 per week;
- sweet, confectionery – 10-15 g per day.
90,068 bread, cereals, pasta – 120-150 g per day;
Memo on the organization of nutrition in the prevention of cardiovascular diseases in children
- Correctly calculate the proportions – the ratio of proteins, fats and carbohydrates should be 1: 1: 4, respectively.
- Do not give a child to eat for two if he is engaged in the sports section.
- It is necessary to increase the amount of proteins and carbohydrates within the previous serving. In a healthy portion, the child needs to limit the level of carbohydrates – doze sweets, consume sugar – 50 g per day.
- Do not oversalt food – excessive salt intake threatens the risk of high blood pressure.
- Avoid the use of chips, nuts, fast food, canned food and other prohibited products.
With proper nutrition, the child’s body weight should correspond to his age. Such tables can be found on the Internet, and doctors use the index of body mass index. Exceeding 25 units already indicates overweight, and higher numbers (27 and above) are a signal of obesity.In order to prevent weight gain, preventive weighing is first of all important. They are carried out when contacting the clinic, as well as in preschool and school institutions.
Control of excess body weight is extremely important, since excess weight creates additional stress on the heart and blood vessels. If you are overweight, doctors recommend revising the diet, balancing the child’s nutrition, reducing fat intake and adjusting the BJU ratio. With these measures, you can achieve the optimal weight loss rate for children – 500 g per week with overweight about 10 percent of the total body weight.
Active lifestyle
For the prevention of cardiovascular diseases, preschool children should be dosed in physical activity. A two-year-old needs at least thirty minutes of targeted physical activity three to four times a week. An excellent option would be brisk walking (about 3 km in half an hour), fast dances, outdoor games (volleyball, basketball, tennis), brisk cycling (you need to cover a distance of about 8 km).
It is recommended to minimize hypodynamia where it can be done – walk the baby to the kindergarten or school, and not take the baby by car, replace tablets and phones with active games with friends in the yard.
All these recommendations are relevant for older children – from six to seventeen years old, but their physical activity should be about an hour. To perform systematic exercises, you can enroll your child in the sports section – this will be an excellent combination of your favorite activity and active pastime. Do not orient your child to victory, let him enjoy the training process itself, choose team sports – volleyball, hockey, basketball.
Quitting smoking
It would seem that it is inappropriate to talk about smoking cessation in childhood.Russian statistics on this issue are inexorable, and this is what makes us talk about smoking in childhood.
According to the numbers, the first attempts at smoking occur at about twelve years old, and if a successful attempt, half of the boys and a quarter of the girls have a smoker experience by the end of school.
This is absolutely unacceptable in a highly developed society, most European countries have already experienced a “cigarette boom” and have chosen a healthy lifestyle. For the post-Soviet countries, this problem is still relevant, therefore, the prevention of diseases of the cardiovascular system in children includes mandatory anti-nicotine propaganda.
Not the last place is occupied by the issue of passive smoking. The child gets almost as much smoke next to the smoking parents as the parents, therefore, in order to prevent cardiovascular pathologies, adults should not smoke themselves, the child should set the right example.
We will separately mention smoking during pregnancy – children whose mothers smoked during gestation are much more likely to have heart and blood vessels, and suffer from other diseases that indirectly affect the normal functioning of the heart.
Based on all the facts, think about the health of the unborn child long before his birth, and when planning a pregnancy:
- give up bad habits;
- do not stand near smokers;
- Choose places for non-smokers in a compartment, cafe, hotel, etc.
Make sure in the future that the child is not under the influence of cigarette smoke, let alone smoked.
Regular examinations of the child
It is important for parents to monitor their basic vital signs from birth.Immediately after birth, the child undergoes his first examinations in his life. If doctors suspect interruptions in the work of the heart and blood vessels, such babies must be referred to cardiologists. Do not neglect examinations if the baby has a pathology – it needs to be diagnosed and treated in time.
Also recommended for healthy children:
- Continuous examinations and monitoring of blood cholesterol levels. Conduct research on children from the age of two.
- From the age of three, constantly monitor your blood pressure – briefly record the results and track the dynamics.If the indicators go beyond the permissible limits, examine the child carefully and identify the cause of the deviations.
In the presence of deviations or a threat of cardiac pathology, the doctor will prescribe drugs and vitamins. Among vitamins, they have proven themselves well:
- Vitrum – contains 14 vitamins and 17 minerals, essential primarily for the normal functioning of the heart. For prevention, you need to drink one tablet at a time. The course of admission is 1-2 months;
- Triovit – Includes three powerful heart vitamins A, E and C, as well as selenium.These substances actively resist atherosclerosis, have a beneficial effect on the work of the heart, and are a good prevention of cardiac pathologies;
- Carnitine – L-Carnitine is an essential amino acid for the heart and helps convert fat into energy. Carnitine is produced in the body on its own, with pathologies of the heart, the risk of cardiological diseases, the amino acid becomes insufficient, therefore it is recommended to take 1 tablet of pure carnitine 2 times a day, or take it as part of Cardonat on the recommendation of a doctor;
- Amosov’s blend is a unique vitamin cardiological blend for normal heart function.In equal quantities, you need to twist raisins, dried apricots, dates, walnuts, prunes in a meat grinder, add lemon juice and honey and take a tablespoon once a day
Children’s drugs for prevention are primarily Korilip, Kudesan, Elkar, Vetoron, folic acid:
- Corilip – rectal suppositories, one candle per day is recommended for children under 6 years old, 1-2 pieces for older children. The course of therapy is 10 days, if necessary, the prophylactic reception is repeated after 2 months;
- Kudesan is a coenzyme complex, it is recommended to take it at 0.5-1 ml (10-20 drops) per day, dissolved in warm water.Frequency rate of admission – twice a day. Prophylaxis with the drug is 10 days, doctors recommend two preventive courses per year;
- Elkar is a preventive cardiac drug. Children under three years old are prescribed 5 drops of the drug twice a day, from 3 to 6 years old – 10 drops, and from 6 to 12 years old – 15 drops of the drug. It must be taken 30 minutes before meals. Prophylaxis with the drug is one month. For children with high sports loads, the doctor may increase the dose of the drug;
- Vetoron is a general health-improving agent.Actively affects the heart muscle and blood vessels, makes them more resilient. It is recommended to drink 10 drops of the drug as a prophylaxis. Vetoron is used immediately after a meal, the duration of the course is 2-4 weeks;
- Folic acid – a drug to improve the functioning of the heart, is necessary for children of any age. The dosage for preschool children is 75 mcg per day, from 6 to 10 years of age – 100 mcg, from 10 to 14 years old – 150 mcg per day.
Strengthening immunity and prevention with folk remedies
It is possible to strengthen the heart not only with medicines, but also with folk remedies.For the work of the heart, grapes will be useful for children. It can be given in any form up to 100-150 g per day several times a week. Grape juice, grape pulp will be useful, and in winter you can include raisins in the diet – add to cereals, baked goods.
In order to strengthen the work of the heart, teach children to parsley. It can be added to salads in the summer, and in winter it is recommended to freeze the parsley and add it to the first courses. Potatoes have a beneficial effect on the work of the heart – mashed potatoes can also be seasoned with parsley.
Recommendations – Regional Narcological Dispensary
Monday,
eight
June
2015
It is generally accepted that heart disease is the lot of the elderly. Young people rarely think about their hearts, but in vain. First, the young will also grow old someday. In old age, a person will have the heart that he deserves with his lifestyle. After retirement, you will want to relax, travel, enjoy life, and not spend all your time in the hospital.The heart must be protected from a young age!
Secondly, statistics show that cardiovascular diseases are rapidly growing younger. After 35 years, heart disease is diagnosed in every tenth. And the higher the age, the more people with heart disease.
Prevention of heart disease is an important topic. Everyone should know how he can harm his heart and how to protect it. You should not treat this carelessly and indifferently – you need to be aware that cardiovascular diseases are the main cause of death in Russia, regardless of age group.And not only in Russia. It is not for nothing that heart disease has been nicknamed “the modern plague.”
The main causes of heart disease
and prevention of cardiovascular diseases
1. Smoking. By lighting a cigarette, a person causes the greatest harm to his heart. The smoker’s heart has to work very hard, and in not the best conditions.
When a person inhales tobacco smoke, the oxygen concentration in the blood decreases.To prevent oxygen starvation, the heart begins to work harder, trying to overtake the higher volume of blood. Figuratively speaking, the heart is working above normal. But in the process of smoking, there is also a spasm of blood vessels, including those that feed the heart. It feels hungry, while forced to work at full strength.
How long will a man who is starved and forced to work twice as long as he is used to hold out? Of course not. So a smoker’s heart can not stand it, which often happens.
Smokers are 70 times more likely to develop cardiovascular disease than non-smokers. Within a year or two after quitting smoking, the risk will decrease to the level of non-smokers.
The first measure to prevent cardiovascular disease is to quit smoking.
2. Obesity. This is the second most common cause of cardiovascular disease. Obese people have weakened muscles. The heart is also a muscle, and in obese people it is weak and flabby.
But this weak heart has to work for two or even three. After all, the higher the weight of a person, the greater the volume of blood that the heart has to distill.
In obese people, cholesterol plaques are deposited in the vessels. Blockage of blood vessels leads to the fact that the heart lacks oxygen.
Imagine: a weak muscle that is undernourished is forced to work in double or triple volume. How long will it last? No!
The upper limit of the normal BMI (body mass index) – 25.If the BMI is higher than only one, the risk of developing heart disease increases by 8-10%. With each unit of BMI, the risk increases. For those whose BMI is 30 or more, the risk of myocardial infarction becomes critical!
For every kilogram you lose, your risk of heart failure and atherosclerosis is reduced.
The second measure to prevent heart disease is to get rid of extra pounds.
3. Drinking alcohol. With alcohol, the body receives a dose of toxins. To remove them from the body, the heart has to pump more blood. The “motor” simply wears out.
It is widely believed that red wine is even good for the heart and blood vessels. The fact is that red wine contains polyphenols that help lower cholesterol levels. However, not everything is so rosy.
First, the body receives a dose of toxins with wine, which creates an unhealthy load on the heart and blood vessels.Plus, alcohol is bad for the liver. Polyphenols can be obtained not with wine, but, for example, with grape juice or green tea. These drinks will only be beneficial.
Regular use of red wine supposedly for the health of the heart and blood vessels is not worth it, otherwise it will turn out as in the saying: “we treat one thing, we cripple the other.” But if you are sure that things will not go further than one glass, sometimes you can pamper yourself.
The third measure for the prevention of heart disease is not to abuse alcohol, try to take it as little as possible.
4. Excessive use of drinks that stimulate the nervous system. Coffee, energy drinks, strong black tea and alcohol increase heart rate. The heart is overloaded and wears out quickly.
You need to know when to stop in everything. Small amounts of coffee and tea are beneficial, but if you constantly drink strong coffee every day, your heart will not stay healthy for long.
“Coffee lovers” should, firstly, reduce the dosage of coffee in drinks.Milk softens the effects of caffeine. You can try chicory. At least sometimes it is worth replacing coffee with weak tea, mineral water, juices .
Energy drinks should not be consumed all the time! These are drinks for special occasions when it is very important to be cheerful (for example, if you need to drive at night). Daily use of energy drinks is a 100% chance of developing heart disease.
The fourth measure for the prevention of heart disease is to reduce the consumption of drinks that excite the nervous system.
5. Sedentary lifestyle. If a person moves a little, the heart becomes “lazy” and weak. Any increase in the load on him can be fatal.
The heart must be trained continuously. Physical activity that trains the heart is called “cardio training”. Running, exercising on a stationary bike or ellipsoid, cycling and skiing, playing sports, swimming – any of these activities, if they are regular, will make your heart stronger and more enduring.However, walking will be enough, but at a fast pace and over decent distances. The main thing is to move regularly. The load should be increased gradually, giving the heart the opportunity to get stronger.
The fifth measure for the prevention of cardiovascular diseases is to lead an active lifestyle, exercise.
6. Eating a lot of salt and “bad” fats. Nutrition is important, and it’s not just weight.
Abuse of animal fats (fatty meat, butter, lard) harms the heart and blood vessels, as it leads to the appearance of atherosclerotic plaques.But fish and vegetable fats, on the contrary, help reduce the level of bad cholesterol. These fats contain omega acids that have a beneficial effect on the heart. To get enough Omega, you need to eat fish, nuts, olives, olive oil and flaxseed oil.
You shouldn’t give up meat completely, especially at a young age. However, you need to alternate between eating meat and fish. Sometimes the meat should be replaced with nuts (for example, instead of the second chop for lunch, eat a handful of nuts).
Instead of pork and fatty poultry, you often need to eat chicken, turkey, veal, rabbit meat. It is better to refuse sausages altogether.
With regard to salt, consuming large amounts of it increases body fluids. Blood volume increases and the heart becomes overwhelmed. Of course, it is not necessary to switch to a salt-free diet, but marinades, salted fish and smoked meats should be consumed less often.
The sixth heart disease prevention measure is to reduce salty foods and animal fats in the diet.
7. Untimely treatment of teeth and tonsillitis. This fact is not known to everyone, unfortunately. The fact is that the presence of chronic sources of infection in the body leads to long-term bacteremia, as a result of which ischemic heart disease and inflammation of its inner lining can develop.
Endocarditis is an inflammation of the inner lining of the heart. People sometimes call the disease “a cold of the heart.” With endocarditis, the likelihood of death is very high.But even if the treatment is successful, irreversible changes will occur to the heart. Therefore, this disease must be prevented. How? Timely eliminating foci of chronic infection.
The most common cause of endocarditis is dental problems, namely periodontitis (inflammation of the tissues surrounding the root of the tooth). Teeth need to be treated on time, in no case starting the process.
If sore throat has become chronic, it also needs to be treated by contacting a doctor. You may need to have a tonsillectomy (removal of the tonsils).
The seventh measure for the prevention of heart disease is the timely sanitation of foci of infection.
The heart doesn’t like that. What drinks harm the main organ | HEALTH: Medicine | HEALTH
Not only certain foods and dishes, but also drinks are useful for heart health. What helps to protect the walls of blood vessels and protect them from blood clots, and what is better to exclude from your life forever, learned the correspondent of “AiF – Tyumen” .
Arrhythmia and death
Frequent consumption of caffeinated beverages is definitely a bad habit for the heart. When drinking coffee, the rule is that everything is good in moderation, so you should not abuse it. It is important to remember that this invigorating drink is not recommended for pregnant women, as well as for certain diseases of the gastrointestinal tract and cardiac arrhythmias. If there are no contraindications, then drinking 1-2 cups of natural coffee in the morning is not prohibited.
Coffee should not be overused. Photo: pixabay.com
“Caffeine is also found in tea and energy drinks. In weak tea, of course, it is much less, but it must be remembered that this drink has a vasodilating and diuretic effect. Moderate consumption of green tea can be associated with preventing the risk of developing cardiovascular disease. This, by the way, is the best option in the heat. Green tea contains antioxidants that regulate cholesterol metabolism, unlike black tea and coffee, it does not have tannins that increase the heartbeat, – comments Elena Pavlovna Gultyaeva, head of the advisory department of the Tyumen Cardio Center .- But it is better to exclude energy drinks altogether – there is as much caffeine in one can of energy drink as in one cup of double espresso. Energy drinks, when consumed regularly, can cause serious heart problems such as sudden or unexplained death, arrhythmias, and heart attack. ”
Green tea is the best option in the heat. Photo: pixabay.com
By a glass?
Alcoholic drinks lower blood pressure during consumption. And if a person is already taking medications, for example, for hypertension or any other that act on blood vessels, then this can be dangerous.Such an increase in the effect will lead to an increase in pressure and impaired circulation.
If we are talking exclusively about festive feasts, then you need to choose one type of alcohol and consume only it. The addiction to drinking shortens life, leads to obesity, cirrhosis, pancreatitis and various types of cancer – tumors of the esophagus, liver, larynx, intestines.
“Alcohol is addictive with all the ensuing consequences. Due to the large amount of drinking, blood pressure rises, the muscles of the heart weaken, and heart failure develops.Therefore, most doctors and medical organizations do not recommend alcohol, including small doses, allegedly for the prevention of diseases of the cardiovascular system. Champagne and sparkling wines are especially harmful. Even low-alcohol drinks, such as beer, are categorically contraindicated for people with heart disease. There is no study of the long-term effects of alcohol on the body. It cannot be said with complete certainty that there is a positive effect of regular alcohol consumption (even a glass of wine a day) on health.If you have problems, if you are predisposed to addiction, then alcohol will do more harm than help, ”the specialist says.
Enemies and Friends
Plain clean water helps the kidneys to eliminate toxins, while retaining nutrients and trace elements.
Plain water is the best way to quench your thirst. Photo: pixabay.com
It’s no secret that sugary carbonated drinks and juices are very high in calories and contain a lot of sugar, they increase the load on the body and the pancreas, and imperceptibly contribute to gaining excess weight.Plus, soda doesn’t quench your thirst. Many sodas contain high amounts of syrup, high in sweeteners that disrupt carbohydrate and lipid metabolism, and this is a direct road to type 2 diabetes or heart problems, as well as kidney, teeth, skin, breathing, etc.
Better to eat the fruit itself than drink a glass of juice
“Fruit juices are also enemies. It is better to eat the fruit itself than to drink a glass of juice.
It is useful to drink salted carbonated water (or just mineral water), but after consulting a doctor, it saturates the body with electrolytes, however, there are contraindications: such water cannot be drunk regularly, in some cases it is prescribed only according to indications, because it works almost like a medicine “, – the cardiologist comments.
The heart loves milk, cottage cheese and other “milk”. Photo: pixabay.com
For the heart, as for all organs, a complete balanced diet is important, and dairy products are rich in microelements.The most important of these for the heart to function are magnesium and potassium. Most of them are found in cottage cheese, yogurt, hard cheese and milk. Consuming these foods regularly leads to overall health benefits. This also affects the heart, it reacts to all processes in the body, to lifestyle and nutrition. Dairy products must be present in the diet, but taking into account individual tolerance, of course.
For drinks from rosehip and hawthorn, from dried fruits, compotes from fresh fruits, berry fruit drinks without sugar – the heart will also thank you.
Many phyto-assemblies are also useful, they dilate blood vessels and normalize blood pressure, minimize the amount of bad cholesterol, make life easier for blood vessels, accelerate blood clotting and stimulate immunity due to the high content of vitamin C. In addition, they often contain many trace elements necessary for the heart muscle.
Rosehip drink is good for the heart. Photo: pixabay.com 90,000 Green tea reduced the risk of early death in stroke and heart attack survivors – Science
TASS, February 4.Cardiologists from Japan have shown that drinking large amounts of green tea can significantly reduce the likelihood of premature death in people who have had strokes and heart attacks. The findings of scientists based on monitoring the health of over 46 thousand people in Japan for two decades, published in an article in the journal Stroke.
“Our observations show that drinking one to six cups of green tea a week reduced the chances of death for victims of strokes and heart attacks by 27%, and drinking seven or more cups reduced these chances by 60%.It is important to understand that in Japan green tea is usually consumed without sweeteners, while the Japanese usually add milk and sugar to coffee, “said Osaka University professor Hiroyasu Iso, quoted by the magazine’s press service.
ISO and his colleagues monitored the health of over 46,000 Japanese people as part of the JACC monitoring project, aimed at studying the risk factors that contribute to the development of cancer.
Benefits of tea and coffee
Participants of this initiative, whose age ranged from 40 to 79 years old, underwent regular examinations and were under constant supervision of doctors.In total, over two decades of JACC’s work, its members have experienced 9.2 thousand strokes, heart attacks and other serious failures in the work of the heart and blood vessels that threaten human life.
Professor Iso and his colleagues used this data to evaluate how the diet of JACC participants affected their likelihood of dying after they had their first stroke or heart attack. This analysis showed that the frequency of consumption of two types of drinks – green tea and coffee – greatly influenced the life expectancy of “heart” and people who had not previously suffered from cardiac problems.In particular, drinking very large amounts of green tea, more than seven cups a week, reduced the chances of premature death by 60% for those Japanese who had suffered strokes or heart attacks in the past. At the same time, tea was not so useful for people who did not suffer from heart disease – its use had almost no effect on their life expectancy.
Whereas coffee significantly reduced the likelihood of death for people without heart problems, reducing the chances of them dying prematurely by about 18% when consumed more than two cups a day.Likewise, coffee reduced the likelihood of having another heart attack by 40%, but had no effect on the incidence of strokes.
What this is connected with, scientists cannot yet say. Professor Iso and his colleagues hope that further observations and experiments on animals will help them understand which components of coffee and green tea have the most positive effect on the health of the heart and brain vessels.
World statistics
Strokes and other forms of cerebral hemorrhage today have become one of the main causes of premature death of people in most developed countries of the world, along with heart attacks, heart failure and various forms of cancer.According to WHO statistics, about 15 million people annually become victims of strokes, of which five million die, and another five become disabled. A significant part of strokes, as experts of the organization now suggest, are associated with high blood pressure and bad habits, which in theory allows them to be prevented by adjusting the behavior and eating habits of people at risk. Likewise, many of the severe consequences of a stroke are associated with the fact that the patient is not provided with timely medical care.
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