How can certain teas impact heart health. Which teas provide the most cardiovascular benefits. Are there any potential risks associated with tea consumption for heart health. What are the key factors to consider when choosing heart-healthy teas.

The Heart-Healthy Benefits of Tea Consumption

Tea has long been celebrated for its potential health benefits, particularly when it comes to cardiovascular health. As one of the most widely consumed beverages worldwide, tea offers a flavorful and potentially beneficial alternative to sugary drinks. But what exactly makes tea so good for your heart?

Dr. Andrew Freeman, director of clinical cardiology at National Jewish Health in Denver, emphasizes the importance of tea as a healthy beverage choice: “There are really only three drinks that I ever recommend humans consume. The best is water, and next would be unsweetened tea and unsweetened coffee. Everything else, unfortunately, doesn’t really have any benefit, and many (when laden with sugar) cause significant harm.”

Key Cardiovascular Benefits of Tea

• Improves cholesterol levels
• Reduces blood pressure
• Lowers risk of heart disease
• Aids in weight management
• Helps regulate blood sugar levels

Research has shown that regular tea consumption, especially when paired with a heart-healthy diet, can have numerous positive effects on cardiovascular health. A 2018 study published in the Journal of the American Heart Association found that tea appears to slow the natural decrease in heart-helping HDL cholesterol as a person ages. This finding complements previous research suggesting that tea can also reduce levels of LDL cholesterol, often referred to as “bad” cholesterol.

Black and Green Tea: The Popular Heart-Healthy Choices

When it comes to heart-healthy teas, black and green varieties stand out as the most popular options, accounting for 99% of tea consumed in the United States. Both types offer significant benefits for cardiovascular health, but what sets them apart?

Comparing Black and Green Tea

Both black and green teas are rich in polyphenols, powerful antioxidants linked to lower blood pressure and improved heart health. While black tea contains more caffeine, green tea boasts a slightly superior antioxidant profile. The choice between the two often comes down to personal preference, as both offer significant cardiovascular benefits.

The Role of Caffeine in Tea’s Heart Health Benefits

Caffeine, a natural stimulant found in tea, plays a complex role in heart health. While it can provide certain benefits, it’s important to understand its effects and consume it in moderation.

Caffeine Content in Different Teas

The amount of caffeine in tea can vary significantly depending on the type and brewing method. A chemical analysis of caffeine content in teas steeped for five minutes revealed:

• Exotica China White tea: 34 milligrams (mg) per 8-ounce cup
• Stash Premium Green tea: 39 mg per 8-ounce cup
• Stash Earl Grey Black tea: 51 mg per 8-ounce cup

These levels are generally lower than those found in coffee, making tea a gentler option for those sensitive to caffeine’s effects. However, it’s crucial to be mindful of your overall caffeine intake, as excessive consumption can lead to anxiety, restlessness, or sleep disturbances.

Potential Risks and Considerations When Consuming Tea for Heart Health

While tea offers numerous benefits for cardiovascular health, it’s important to be aware of potential risks and considerations associated with its consumption.

Iron Absorption and Tea Consumption

One potential concern is the impact of tea on iron absorption. Tea is rich in tannins, compounds that can bind to iron and inhibit its absorption in the digestive tract. This effect is particularly relevant for individuals at risk of iron deficiency. To minimize this issue, consider consuming tea between meals rather than with iron-rich foods.

The Importance of Tea Temperature

The temperature at which you consume tea may also have health implications. Dr. Xiang Gao, director of the Nutritional Epidemiology Lab at Pennsylvania State University, notes: “Some studies found that drinking very hot tea – 140 degrees Fahrenheit or higher – was associated with a high risk of esophageal and/or gastric cancer. So, if you drink tea, do not drink the tea that is too hot.”

Allowing your tea to cool slightly before consumption can help mitigate this risk while still providing the beverage’s heart-healthy benefits.

Maximizing the Heart Health Benefits of Tea

To reap the most cardiovascular benefits from tea consumption, it’s crucial to focus on proper preparation and avoid common pitfalls that can negate its positive effects.

The Danger of Added Sugars

One of the most significant factors that can undermine the heart health benefits of tea is the addition of sugar or other sweeteners. Dr. Freeman warns: “It’s very easy to take a low-calorie beverage and make it incredibly unhealthy by adding tons of sugar or honey.”

He points out the paradox seen in some regions known for high rates of heart disease: “If you go to parts of the South – the stroke belt, so to speak – they actually have a surprising amount of ‘superfoods’ in their diet, but they also have some of the highest rates of heart disease. Why is that? When you adulterate those foods, for instance making sweet tea from regular tea, it ends up with a lot more adverse cardiac outcomes.”

Tips for Heart-Healthy Tea Consumption

• Choose unsweetened varieties of tea
• Avoid adding sugar, honey, or artificial sweeteners
• Allow tea to cool slightly before drinking
• Consume tea between meals to minimize impact on iron absorption
• Be mindful of overall caffeine intake

Exploring Different Types of Heart-Healthy Teas

While black and green teas are the most popular choices, several other varieties offer potential cardiovascular benefits. Let’s explore some of these options:

White Tea

White tea is the least processed of all tea varieties, retaining high levels of antioxidants. It may help reduce the risk of heart disease by lowering cholesterol levels and improving blood vessel function.

Oolong Tea

Oolong tea, partially oxidized, falls between green and black tea in terms of processing. It contains compounds that may help lower cholesterol levels and reduce the risk of heart disease.

Pu-erh Tea

This fermented tea has been shown to have potential cholesterol-lowering effects and may help reduce the risk of heart disease.

Hibiscus Tea

Known for its tart flavor, hibiscus tea may help lower blood pressure and reduce the risk of hypertension, a major risk factor for heart disease.

Incorporating Heart-Healthy Teas into Your Daily Routine

Making tea a regular part of your daily routine can be an effective way to support heart health. Here are some strategies for incorporating more tea into your diet:

Practical Tips for Increasing Tea Consumption

• Start your day with a cup of green or black tea instead of coffee
• Keep a variety of caffeine-free herbal teas on hand for evening consumption
• Replace sugary drinks with unsweetened iced tea
• Use tea as a base for smoothies or other healthy beverages
• Experiment with different tea varieties to find your favorites

Remember, while tea can be a valuable addition to a heart-healthy lifestyle, it should be part of a broader approach that includes a balanced diet, regular exercise, and other healthy habits. Always consult with your healthcare provider before making significant changes to your diet or lifestyle, especially if you have existing health conditions or are taking medications that may interact with tea.

By choosing the right teas and consuming them in a mindful manner, you can harness their potential cardiovascular benefits and support your overall heart health. Whether you prefer the bold flavor of black tea or the delicate notes of green tea, there’s a heart-healthy option waiting for you to explore.

Teatime can be good for your health

Next to water, tea is one of the most popular beverages in the world, and at just a couple of calories per serving, it’s loaded with flavonoids that make it one of the world’s healthiest beverages as well.

“There are really only three drinks that I ever recommend humans consume,” said Dr. Andrew Freeman, director of clinical cardiology and cardiovascular prevention and wellness at National Jewish Health in Denver. “The best is water, and next would be unsweetened tea and unsweetened coffee. Everything else, unfortunately, doesn’t really have any benefit, and many (when laden with sugar) cause significant harm.

“It makes my job very easy when people say, ‘What should I drink?'”

Studies show tea consumption, along with a heart-healthy diet, may improve some brain function, ward off some cancers, defend against heart disease by boosting “good” cholesterol and help with weight control. It may even reduce bad breath.

A 2018 study in the Journal of the American Heart Association found that tea appears to slow the natural decrease in heart-helping HDL cholesterol as a person ages. Those findings pair well with previous research that suggests tea also reduces low-density lipoprotein, or LDL, known as “bad” cholesterol. Studies also show tea may reduce blood sugar levels and help prevent type 2 diabetes.

Black and green tea are the most popular kinds, accounting for 99% of the tea consumed in the United States. Both kinds of tea are loaded with caffeine and antioxidants called polyphenols, which are linked to lower blood pressure and better heart health. There are some slight differences; black tea, for example, contains more caffeine while green tea has a slightly better antioxidant profile.

Experts are quick to point out, however, that tea’s health benefits can be negated if sugar or other unhealthy ingredients are added.

“It’s very easy to take a low-calorie beverage and make it incredibly unhealthy by adding tons of sugar or honey,” Freeman said. “If you go to parts of the South – the stroke belt, so to speak – they actually have a surprising amount of ‘superfoods’ in their diet, but they also have some of the highest rates of heart disease. Why is that?

“When you adulterate those foods, for instance making sweet tea from regular tea, it ends up with a lot more adverse cardiac outcomes.”

While temperature also may seem to be a matter of individual preference, cooler tea may prove to be a healthier choice.

“Some studies found that drinking very hot tea – 140 degrees Fahrenheit or higher – was associated with a high risk of esophageal and/or gastric cancer,” said Dr. Xiang Gao, director of the Nutritional Epidemiology Lab at Pennsylvania State University. “So, if you drink tea, do not drink the tea that is too hot.”

Though experts say tea is a safe, natural beverage that is a better choice than processed, sweetened beverages, there can be negative side effects if a person consumes too much.

For example, drinking too much tea could lead to an iron deficiency because tea is rich in tannins, which can bind to iron and keep it from being absorbed in the digestive tract. Tea drinkers also face the same caffeine-related dangers that coffee drinkers face; too much can cause anxiety, restlessness or trouble sleeping.

Still, tea makes for a healthier beverage choice than juice or soda, provided it’s in its natural form with no added ingredients.

“If you go to your local coffee shop and you order a pink dragonfruit yada yada yada, those are loaded with sugar,” Freeman said. “They’re really delicious, and you see people drinking them, and they think they’re healthy because they contain exotic fruits, but they’re mostly sugar. It is possible to go to a coffee shop and get plain (unsweetened) coffee, plain (unsweetened) tea – or plain green tea for that matter – but you have to really be careful what you’re consuming.”

If you have questions or comments about this story, please email [email protected].

7 Teas That Can Help or Harm Your Heart

Posted on August 29, 2016March 16, 2020 by Erin Meyering

As part of a heart-healthy eating plan, your doctor or nutritionist may suggest drinking more tea — and with good reason. Soothing, aromatic tea has certainly earned a spot on the list of approved foods and drinks for its myriad of mind and body benefits. Significantly lower in caffeine than coffee, the caffeine you’ll get in a cup of tea varies depending on the type of tea, the brand, how it was processed, and how long it steeps. A chemical analysis of caffeine content in teas steeped for five minutes found Exotica China White tea has 34 milligrams (mg), Stash Premium Green tea has 39 mg, and Stash Earl Grey Black tea has 51 mg of caffeine in an 8 ounce cup.

When it comes to health benefits, the type of tea you drink matters, as do any medications you might be taking. You also have to consider your individual caffeine sensitivity. In general, the best types of tea are those made from the Camellia Sinensis shrub: black, white, green, and Oolong.

Black Tea: It’s Both Good and Bad for Your Heart

Black tea is oxidized most extensively; hence its black color,” says Dr. Brill. “Most of the benefits come from powerful plant chemicals known as polyphenols, as well as flavonoids. ” Heart patients who are coffee drinkers should consider switching to black tea because it has roughly half the amount of caffeine as a same-sized cup of coffee. And results of a clinical trial published in the May 2012 Preventive Medicine journal indicated that people who drank three cups of black tea per day had, on average, 36 percent lower triglyceride levels and a 17 percent improvement in their cholesterol profiles.

All black teas are caffeinated, which is not great if you have high blood pressure or a fast heart rate — it can make things worse. For black teas, you may expect anywhere from 14 to 70 mg of caffeine.

Stimulants can trigger heart arrhythmias in some patients. If any teas give you palpitations or a rapid heartbeat, you should stop drinking them and let your doctor know. And use caution if you’re taking Coumadin (warfarin), a commonly prescribed blood thinner, as black tea may decrease blood clotting and increase your chances of bruising and bleeding.

Green Tea: Lower Lipids, Less Plaque

For your heart health, it pays to go green. With green tea, the leaves have been harvested and allowed to wither, and then steamed. There is no oxidation. We recommend choosing green tea as often as possible if you’re a tea drinker. Just don’t ruin it with sugar. Clinical studies on drinking green tea have found that it helps lower LDL cholesterol and triglycerides — good news for your heart. And drinking green tea is also associated with a lower risk of heart disease and death from a heart attack or stroke, according to a study of more than 90,000 Japanese participants published in the March 2015 Annals of Epidemiology.

An 8-ounce cup of green tea gives you from 24 to 45 mg caffeine depending on how long it’s brewed. Powerful antioxidants in green tea — especially one called epigallocatechin gallate, or EGCG — can help prevent atherosclerosis, the buildup of plaque in the arteries. The EGCG can also help boost metabolism, helping to make it easier to achieve and maintain a healthy weight. In addition, green tea helps improve the function of endothelial cells in blood vessels.

White Tea: Good for Circulation

White tea is harvested from the young buds of the tea plant and only briefly processed. This is probably the purest tea, and it is recommended for overall heart health. The flavonoids are good for the heart and help dilate the arteries by thinning the blood, lowering blood pressure, and reducing bad cholesterol. White tea may help protect not just your heart, but also the entire circulatory system.

But double-check with your doctor if you’re taking a blood thinner like Coumadin or are sensitive to caffeine. White tea does contain caffeine, which can speed your heart rate or increase your risk for high blood pressure.

Oolong Tea: Lower Cholesterol and a Warfarin Warning

Crushed tea leaves that have been oxidized for a period of time, and then heated to stop the process, makeup Oolong tea. One clinical study on Oolong tea found that it may help lower cholesterol levels in patients with coronary artery disease, though more research is needed to be certain. In animal studies, Oolong appeared to reduce triglycerides and food intake, though there is not yet a lot of data on Oolong and its cardiac effects.

Always talk to your doctor if you plan to drink Oolong, especially if you take a blood thinner like Coumadin. People who take those medications must tell their doctors everything they are taking — every herb, supplement, vitamin, and so on. And that includes tea.

Chamomile Tea: Sleep Enabler

Though herbal teas do not come from the traditional tea plant, they still have some health benefits; such as soothing herbal teas like linden or chamomile. These teas help with a less-direct, but still crucially important, benefit for cardiac wellness: sleep. One of the things many of my patients have issues with is getting enough sleep. Sleep is such an important part of restorative health for everyone. Try getting into the habit of having a nighttime routine to wind down, and include a cup of warm chamomile tea right before bed.

Patients with a coronary artery stent, or who are taking aspirin or Coumadin (warfarin) blood thinners, should consult their doctor before drinking chamomile tea, because it may increase the risk for internal bleeding.

Ginseng Tea: Natural Blood Thinner

Though ginseng has not been formally evaluated by the Food and Drug Administration, drinking it may potentially give a boost to your heart. Studies do support that ginseng may lower blood pressure by relaxing the arteries. It thins the blood by blocking platelet adhesion, and it may improve cholesterol profiles. Consider ginseng tea a tasty replacement for a more sugary beverage, which also has heart-boosting benefits. Replace that sugar-loaded sweet tea with a glass of brewed ginseng tea instead. Not only will this provide you with a slimming benefit, but it will also reduce your intake of excess sugar, which can damage your heart.

As with most teas, talk to your doctor if you’re taking blood thinners like Coumadin or anti-platelet drugs such as Plavix (clopidogrel).

St. John’s Wort: Risky Combined With Heart Meds

You may have heard that the St. John’s Wort herb can help treat symptoms of depression but be wary of drinking this tea if you have a heart condition. The biggest concern is that it’s not good with cardiac medications. The ingredient is “epically dangerous” if you’re taking blood thinners or cardiac medications for heart failure, like digoxin, or if you require a stent or have atrial fibrillation.

If you’re considering drinking St. John’s Wort tea for depression, talk to your doctor instead. There’s such a close association between depression and heart disease.

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Health Benefits of Drinking Tea For The Heart

Is it possible that a daily cup of tea can protect you against cardiovascular disease? Let’s learn more about drinking tea for heart benefits.

Recent studies have shown that regular tea drinkers have a lower risk of developing arterial stiffness in the heart, which has been linked to a higher risk of cardiovascular disease.  Further studies have indicated with evidence that drinking tea helps reduce high cholesterol consequently cutting down the risk of possible heart diseases.

The Flavonoid Flavour

Tea is a major source of flavonoids, which act as potent antioxidants that neutralize the body’s naturally occurring, but cell-damaging free radical molecules. Research has shown that tea flavonoids may help promote heart health by improving blood vessel and endothelial function, and by improving cholesterol levels.

High blood cholesterol is a major risk factor for heart disease and stroke. It can lead to a build-up of plaque in the artery walls and narrow the arteries. Black tea may help reduce the risk of heart disease by helping maintain healthy function of the endothelium, the inner lining of blood vessels. Phytochemicals in tea may increase the artery’s ability to dilate thereby improving coronary vessel function.

Black or Green?

Daily tea consumption has been shown to lower the risk of having a heart attack and improve the likelihood of surviving a heart attack. While much of the strongest research supporting tea’s potential to contribute to heart health has focused on black tea, new research has shown that green tea also offers cardiovascular benefits.

Is green tea good for your heart?

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. Green tea catechins also work together to lower cholesterol.

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 called tannins that have their own heart-health benefits.

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 best varieties for your heart.

What kind of tea is good for the heart?

If you are an avid tea drinker and are curious to know more about teas for the heart, then you should know that it all depends on the type of tea you drink. The best types of tea are those made from the Camellia sinensis shrub that is good for your heart.

Tea for high blood pressure

You’ll be surprised at the benefits tea has to offer. A cup of tea can help decrease the risk of hypertension and lower blood pressure. Drinking herbal tea for high blood pressure is also recommended. Here is a list of best teas for high blood pressure:

• Green tea
• Hibiscus tea
• Nettle Tea
• Java tea

Drinking Herbal tea for heart health

Certain types of herbal tea can help with heart health, Herbal tea like Rooibos, Sage, Lemon balm and hibiscus tea are good for improving heart health.

Check out the New Wellness Teas Collection at Teabox

Just tea is not enough

When it comes to health benefits, the type of tea you drink matters, especially if you are taking regular medication. You also have to consider your individual caffeine sensitivity.  While drinking tea may aid in your battle against heart disease, the most important factors are your diet and lifestyle. So eat healthy, work out and then grab a refreshing cup of tea to boost your cardiovascular health.

Will drinking green tea reduce my risk of heart attacks and strokes?

According to the news headlines, drinking green tea could prevent deaths from heart attacks or strokes. We look behind the headlines.

1 June 2018 

A compound found in green tea could help break up plaques that are linked to dangerous blockages, researchers suggest.

The research, part-funded by the BHF, found that a compound in green tea can break up and dissolve potentially dangerous protein plaques found in the blood vessels.

But before you reach for the kettle, it is important to know that to get effective amounts of the compound (called EGCG) into the bloodstream by drinking green tea, you’d need to drink enormous quantities of it – which is not what the researchers are recommending.

The researchers are now looking at other ways that the compound could be used. This could involve changing the chemical structure of EGCG, making it easier to be absorbed from the stomach and more resistant to your metabolism, or developing new methods to deliver the molecule to the plaques – for example via an injection.

The BHF view

Swapping your cuppa for green tea is unlikely to make a big difference with respect to your heart health. 

Professor Jeremy Pearson
BHF Associate Medical Director

Professor Jeremy Pearson, Associate Medical Director at the British Heart Foundation, said: “Our bodies are very good at breaking down EGCG, so swapping your cuppa for green tea is unlikely to make a big difference with respect to your heart health.

“But by engineering the molecule slightly, we might be able to make new medicines to treat heart attack and stroke.”

If you want to reduce your risk of heart and circulatory diseases the best way is by adopting a healthy active lifestyle, eating a balanced diet, not smoking, and maintaining a healthy weight, rather than by focusing on a single food or drink.

How was the research carried out?

Atherosclerosis is the build-up of fatty material inside our arteries that can reduce the flow of blood to the heart and brain, and can lead to heart attacks and strokes. In advanced stages of atherosclerosis, a protein called apolipoprotein A-1 (apoA-1) can form amyloid deposits, which are similar in structure to those associated with Alzheimer’s disease. These deposits build up within atherosclerotic plaques. Here, they increase the size of the plaques, further restricting blood flow, and may also make the plaques less stable, increasing the risk of a heart attack or stroke.

The scientists, from Lancaster University and the University of Leeds, have discovered that EGCG, binds to the amyloid fibres of apoA-1. This converts the fibres to smaller soluble molecules that are less likely to be damaging to blood vessels.

The findings can’t be applied to people yet, so we cannot say that drinking green tea is good for you

A weakness of the research is that it was carried out in a laboratory rather than real-life setting. This is as the effect of EGCG could not be demonstrated in humans because the compound is poorly absorbed and quite unstable in the body . While the lab setting means that the results are more reliable as the study can be more carefully controlled, the findings can’t be applied to people yet, so we cannot say that drinking green tea is good for you. 

The chemists also carried out a complex process to prepare the green tea, in order to isolate certain compounds from the green tea, which wouldn’t be done at home. A household brand of green tea was added to a small amount of water (40ml, whereas a mug of water is around 350ml).  The solution was microwaved for six cycles in total, of either 30 or 15 seconds, with a minute in between, and then filtered twice and freeze-dried until further use.

People who had the flavanol drink had lower blood pressure, lower cholesterol levels and less arterial stiffness than the control group. The study’s authors say that this would lead to a lower risk of coronary heart disease, including , and cardiovascular disease.

The media coverage

The research was covered in The Independent, The Guardian and The Mirror.The Guardian’s coverage was good, and make it clear in the first paragraph that the researchers weren’t recommending that everyone drinks green tea to reduce their risk of heart attacks.

The Independent’s story was more sensational, stating that ‘Green tea could hold the key to preventing thousands of deaths each year caused by strokes and heart disease.’ It did acknowledge that more research was needed, but didn’t make it clear that this was research done in test tubes, not in humans, and we can’t say from this research that drinking green tea will have the same effects in the human body.

So is green tea good for me?

Claims have also been made that green tea can help with weight loss, and protection from cancer and Alzheimer’s disease

There have been claims that green tea can help lower your cholesterol and blood pressure. A good-quality review from 2011 found drinking green tea enriched with catechins led to a small reduction in cholesterol.

Similarly, a 2013 review of 11 studies found that having green or black tea daily (either as a drink or capsule) could help lower your cholesterol and blood pressure. But most of the clinical trials they included in this review were short-term, so the authors cautioned that longer term trial were needed to back up their findings. 

A 2014 survey of data from previous studies found evidence of a small reduction in blood pressure for people with high blood pressure who consumed green tea. But it is unclear whether this reduction was significant enough to reduce your risk of heart problems or stroke.

Claims have also been made that green tea can help with weight loss, and protection from cancer and Alzheimer’s disease, but there is a lack of evidence to support these claims.  

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 10^th 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

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

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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These Teas Can Help You Manage Hypertension Naturally

High blood pressure: Some effective home remedies can help you manage hypertension naturally

Highlights

• High blood pressure can trigger the risk of cardiovascular diseases
• Simple dietary changes can help in improving blood pressure numbers
• The goodness of teas can make it easier for you to manage blood pressure

High blood pressure or hypertension is so common its almost become like an epidemic. Poor eating habits, lack of physical activities, work pressure, increased stress are some of the contributors to high blood pressure and the list is long. There are multiple health issues linked with high blood pressure. It is one of the leading causes of cardiovascular diseases. Hypertension should not be ignored and requires treatment on time. Natural remedies for hypertension can help in controlling blood pressure numbers. Some foods for high blood pressure work well especially fibre rich foods. Similarly, there are certain teas which can help you control blood pressure. Your morning cup of tea now can make it easier for you to manage blood pressure. Teas for high blood pressure are loaded with other health benefits as well which will result in better overall health.

Healthy Teas for high blood pressure

1. Green tea

Green tea is loaded with health benefits. It is widely consumed to enhance the weight loss process. Green tea can help in controlling high blood pressure. Consumption of green tea improves the flow of blood. It also reduces inflammation in the heart tissues. Green tea is loaded with antioxidants which also improves heart health. If you have high blood pressure you can drink a cup or two of green on a daily basis, but do not over consume it.

Also read: High Blood Pressure: Top 10 Foods To Lower Your Blood Pressure

2. Hibiscus tea

The beautiful red leaves of hibiscus flowers are used to prepare tea which is good for high blood pressure. It also contains antioxidant properties which promote heart health. Various studies have also examined the positive effect of hibiscus tea in blood pressure. But it is advised to consult your doctor before adding hibiscus tea to your diet to check its suitability with the medicines you are taking. Hibiscus tea can also promote weight loss and liver health. But if you are a hypertension patient make sure that you consult your doctor for dosage.

Teas for high blood pressure are rich in antioxidant which can improve heart health
Photo Credit: iStock

3. Oolong tea

Oolong tea has properties of dark and green tea. It is not well known but is loaded with health benefits. This tea is again rich in antioxidants which make it good for heart health. You can find oolong tea near you or online but take advice from your doctor before consuming it.

Also read: Manage Your High Blood Pressure With Fibre Rich Foods: Know Best Food Sources Of Fibre

Other ways to manage blood pressure

Blood pressure needs regular practice to keep it normal. You need to follow other healthy practices to manage blood pressure. Some of them are:

• Reduce bodyweight if you are overweight
• Quit smoking
• Eat a healthy and nutritious diet which is loaded with fibre
• Exercise regularly at least for 30 minutes
• Limit your alcohol and caffeine intake

Also read: Have High Blood Pressure? One Cup Of This Fruit Can Help Bring It Down! Here’s How

Disclaimer: This content including advice provides generic information only. It is in no way a substitute for qualified medical opinion. Always consult a specialist or your own doctor for more information. NDTV does not claim responsibility for this information.

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Drinking tea may improve your health — here’s what to try

No matter what the season, tea can be a tasty beverage since it can be served iced or hot.

But its benefits go far beyond refreshment. There is plenty of research showing that drinking tea can actually improve your health.

A recent study, published in European Journal of Preventive Cardiology, involved more than 100,000 adults in China and found those who regularly drank tea were less likely to develop atherosclerotic cardiovascular disease or die prematurely from any cause — particularly stroke — compared to others during a seven-year follow-up.

The link was especially strong among habitual tea drinkers — those who enjoyed the beverage at least three times a week. Green tea seemed to have a stronger effect than black tea.

Based on the findings, a 50-year-old frequent tea drinker might develop heart disease almost a year-and-a-half later or live about a year longer than someone who never or seldom drank tea, the study authors wrote.

The results suggest habitual tea consumption may be considered “as an overall health-promoting lifestyle behavior,” wrote Vanessa Bianconi, a researcher at the University of Perugia in Italy and lead author of an editorial accompanying the new research.

Tea’s ability to lower blood pressure may be why it could reduce a person’s risk of dying of a stroke, the editorial noted.

Tea, especially green tea, is a rich source of flavonoids, bioactive compounds that can lessen oxidative stress, relieve inflammation, and provide other health benefits, the study authors noted. They cautioned more research was needed to see whether the results in Chinese adults would also apply to people outside east Asia.

Related

Other studies have shown teas can help protect your teeth and your heart, as well as possibly even helping to stave off cancer. At the very least, drinking tea is a flavorful way of getting enough fluid into your body each day.

Which type you drink can make a difference. All non-herbal teas are made from the leaves of the Camellia sinensis plant. The amount of time the leaves are processed determines whether you end up with a green, black or oolong tea.

The green teas are the least processed and tend to have the highest amounts of polyphenols, and the only type that contain the polyphenol, catechin, which is why many studies have been done using only green teas. Certain herbal teas are known for their medicinal values, including soothing the digestive system.

Here are the top 10 health benefits of tea and some options for delicious teas to try:

1. Tea contains antioxidants.

Antioxidants work to prevent the body’s version of rust and thus help to keep us young and protect us from damage from pollution. Load up on antioxidants with a white tea, which is less processed than black or green tea so it retains more beneficial antioxidants.

Vahdam Himalayan Imperial White Tea

2. Tea has less caffeine than coffee.

Herbal blends have no caffeine, while traditional teas have less than 50% of what typically is found in coffee. That means you can consume it without those pesky effects on your nervous system, says Leslie Bonci, nutritionist and owner of Active Eating Advice. If you’re trying to switch from coffee to tea, try a chicory root tea like Teeccino, which has a mouth feel and flavor similar to coffee. Chicory root is also known to help reduce stress and is a prebiotic so may be helpful to your gut.

Bonus: this tea will give you a kick of energy without the caffeine.

Teeccino Herbal Coffee Tee-Bags

3. Tea may reduce your risk of heart attack and stroke

“There’s a lot of literature out there on tea and heart health,” said Anna Ardine, clinical nutrition manager at Magee-Womens Hospital of the University of Pittsburgh Medical Center. “This is a health effect for which there is the strongest evidence.”

In fact, a study published in 2016 that combined data from a host of earlier reports found a nearly 20% reduction in the risk of heart attack and a 35% reduced risk of stroke among those who drank one to three cups of green tea a day. Those who drank four or more cups of green tea daily had a 32% reduction in the risk of having a heart attack and lower levels of LDL cholesterol. Four cups of green tea may keep you running to the bathroom, but you can get the same benefit from drinking one cup of matcha tea, which is made from ground green tea leaves and is said to be the nutritional equivalent of 10 cups of regular green tea.

Starter Matcha 100% Organic Matcha

4. Tea may help with weight loss

Research on this isn’t as strong, Ardine said, adding that studies that have shown an effect have depended on consumption of large amounts of tea, often in pill form.

5. Tea may help protect your bones

Data from recent animal studies has shown that green tea may prevent bone loss. Moringa, a plant that’s native to South Asia, has been known for its medicinal properties and is now quickly becoming a mainstream superfood. With more calcium than milk, as well as iron, vitamin A and K, moringa tea is a great addition to help keep those bones strong.

The Republic Of Tea Organic Moringa Superherb Herbal Tea

6. Tea may keep your smile bright

“Japanese researchers have found that tea can decrease tooth loss,” Ardine said. “It changes the pH in your mouth when you drink it and that may be what prevents cavities.” Beyond that, tea, unlike many other beverages does not appear to erode tooth enamel, Bonci said.

7. Tea may boost the immune system

Studies have shown tea can tune up immune cells so they reach their targets quicker. Holy basil or tulsi tea has been used by Ayurvedic practitioners for centuries to help keep the immune system strong after injuries or illnesses thanks to its antibacterial, anti-fungal and anti-inflammatory properties.

Organic India Tulsi Tea

8. Tea may help battle cancer

Studies on this are currently mixed, which means more research is needed, Bonci says. But, in the meantime, “if you’ve got a strong family history of cancer and you want to do anything you can, you might increase your tea consumption,” she added.

9. Herbal tea may soothe the digestive system

“Herbal teas, in particular chamomile, can be good for people with irritable bowel syndrome because it is an antispasmodic,” Bonci said. “And ginger teas can calm nausea.” Get a dose of both with a ginger chamomile tea.

Traditional Medicinals Organic Ginger with Chamomile Herbal Leaf Tea

10. Tea — unadulterated, that is — is calorie free

“It’s a great no-calorie alternative to water,” Bonci said. “It provides so many options for flavor and versatility. You can have it hot or cold. And you don’t have to put anything in it, though you might want to add a cinnamon stick or some ginger. That means you’re able to hydrate with something other than water alone.”

Get yourself a cannister of Teabloom’s fruit and green tea variety packs and you’ll never get bored — or miss the sugar. With all-natural flavors like pineapple, acai berry, strawberry and litchi, you can easily keep your palate pleased.

Teabloom Flowering Fruit Teas

For more ways to get healthy in 2020, check out our list of favorite healthy cookbooks, our go-to veggie spiralizer that has over 4,000 positive reviews, or our list of the 17 best keto snacks.

TODAY’s A. Pawlowski contributed to this report.

Related:

90,000 Tea for the heart. Black. mate, rooibos and heart herbal tea

Modern scientists say with caution that drinking tea, especially Chinese tea, is good for the heart muscle. Why with caution? The thing is, there is obviously a connection between a cup of tea and heart health. But science has not yet revealed which substances, and in what quantity, improve the function of the arteries.

However, human wisdom, passed through the centuries, coupled with traditional medicine, claims that it’s all about the taste of tea! Namely, in the flavonoid chemicals that give the drink an amazing aroma.They are useful for the circulatory system and heart.

So what teas can have a positive effect on the main organ?

Black and green teas

Due to the caffeine content, drinks stimulate the activity of the heart muscle. Potassium also has a positive effect on the functioning of this organ.

If you suffer from coronary artery disease, then one of the actions of tea will help you: it reduces the amount of muscle metabolic products in the circulatory system, as a result, allows oxygen to fully flow to the heart.

People of age suffer from vascular fragility. Tea, or rather, vitamin P, which it contains, gives the walls of blood vessels strength.

If you have low blood pressure, drink black tea. If it is too high, it is better to choose green.

Mate

The drink contains matein, which is similar in properties to caffeine, but has a milder and more balanced effect for the nervous system. In addition, mate strengthens the vascular walls.

Rooibos

You can drink a caffeine-free beverage without restriction.It reduces blood pressure, energizes the body and even stops the aging process.

Herbal teas

As you know, infusions have been used since ancient times for the treatment and prevention of many diseases. If you want to take care of your heart, then choose teas with the following herbs:

• Hawthorn (has a beneficial effect on tone),
• Valerian (normalizes myocardial tone and size of coronary vessels),
• Mint (relieves pain and vascular spasms),
• Melissa (helps with cardioneurosis),
• Motherwort (reduces pressure and shortness of breath),
• Lovage (strengthens, reduces swelling of the heart).

In any case, whatever drink you choose, the main thing is that it is of high quality, natural, collected with respect and prepared according to all the rules. We offer you such teas!

And remember the precautions: no medicine should be abused!

90,000 health benefits of saffron tea

A miraculous drink with the addition of saffron can improve mood, help with diseases of the cardiovascular system and more.

During the cold period, it is especially necessary to monitor your health. At this time, you need to try to help your body adapt to cold weather and stress. Saffron tea is an excellent remedy for maintaining good health. Why is it so useful? Let’s figure it out.

Will help your heart

Saffron has powerful antioxidant properties. It contains many different chemical components that are very useful in maintaining the health of the body.Saffron is especially necessary for people who have problems with the heart and blood vessels. Due to its medicinal properties, this spice helps to lower blood cholesterol and also significantly reduces blood pressure. Its regular use is an excellent prevention of heart disease.

Save from depression and stress

Drinking at least one cup of saffron-infused tea can cheer you up. This vibrant spice is also called the “sun spice”.And it’s not just about her color. Saffron contains substances that help people fight the symptoms of depression. Therefore, if suddenly you feel that the autumn apathy has decided to recoup you, then just drink tea with saffron – this is another great recipe for a good mood.

Reduces the risk of developing cancer

Few people know, but saffron tea is quite effective in preventing the development of cancer. This is all thanks to the antioxidants and flavonoids that are abundant in saffron.These substances perfectly protect the body from various diseases, including cancer.

Saffron tea will improve memory

For those who have problems remembering some important things, saffron tea will become a “magic pill for memory.” The fact is that this spice is a storehouse of crocin and crocetin – substances that are responsible for brain function and good memory. Therefore, in order to increase efficiency and memorize better, add a little saffron to your tea.

How to make saffron tea

We talked about all the beneficial properties of the miraculous drink – but how to prepare it? In fact, everything is very simple. All you need is to find in the store and buy a spice. Saffron can be brewed without any additives. In this case, just pour boiling water over it and let it brew. If you think the taste is too intense, try diluting it with regular green or black tea. The finished drink goes well with coconut milk and various spices.

Matcha tea – properties, benefits and harms for women, use for the prevention and treatment of cancer

Matcha tea helps burn fat and fight cancer

Looking for a healthy drink for every day? Your search has come to an end. Pay attention to matcha green tea, its possibilities are amazing!

Loved by many nutritionists, researchers, and health-conscious individuals, matcha is no ordinary green tea.This finely ground beverage of high quality has been used in tea ceremonies in Japan for many centuries.

In its ability to cope with excess weight and cancer, matcha is significantly ahead of other types of tea. Thus, a number of studies have shown that the chemical compounds present in the match can cause the death of cancer cells, neutralize the harmful effects of free radicals and support the body’s natural detoxification processes.

What is matcha?

Matcha is a concentrated green tea in powder form that has been drunk for centuries in China and Japan.The word “matcha” is Japanese and means “ground tea”.

Matcha tea is made from the leaves of the Chinese Camellia plant ( Camellia sinensis ) , an evergreen shrub of the Tea family ( Theaceae ) . All tea is made from this plant, however the color and taste depends on the way the leaves are processed.

Tea bushes that are grown for matcha are usually covered from sun exposure for two weeks before harvesting the leaves to increase chlorophyll levels.Then they are doused with steam, dried and milled to obtain a powder.

Unlike other varieties, matcha is prepared from whole leaves, preserving more nutrients. It has a strong and distinct aroma, reminiscent of many spinach or wheatgrass.

All the “power” of tea lies in the polyphenolic compounds of catechins, antioxidants found in green tea, cocoa and apples.

But in the match this substance is especially abundant, and in order to experience its beneficial properties on yourself, the drink should be drunk regularly.It has many potential beneficial effects, from improving heart health to lowering blood sugar levels and fighting obesity.

Health benefits

1. Prevents the development of cancer

Scientists have shown that drinking green tea may reduce the risk of developing cancer. Cancers that matcha can help treat include:

• Bladder cancer. A study of 882 women showed that those who drink matcha tea significantly reduce their risk of bladder cancer.
• Breast cancer. A meta-analysis of several observational studies found that women who drink predominantly green tea had a 22% lower chance of developing breast cancer.
• Cancer of the rectum and colon. A study of 69,710 Chinese women between the ages of 40 and 70 found that green tea drinkers were 57% less likely to suffer from colorectal cancer.
• Prostate cancer. One large study found that Japanese people drinking 5 or more cups of green tea a day reduced their chances of developing prostate cancer by 48%.

2. Promotes weight loss

Several scientific studies show that matcha tea can help to correct the waist and help in the fight against excess weight.

For example, a study appearing in the American Journal of Clinical Nutrition claims that drinking green tea rich in catechins for 12 weeks leads to significant reductions in body fat, decreases in body mass index (BMI), weight and waist circumference. compared with the control group.

Also, a review in the Netherlands showed that catechins in green tea (including matcha) contribute to weight loss.

Another study found that matcha accelerates metabolism and promotes fat burning.

3. Increases the effectiveness of physical exercise

Clinical studies suggest that matcha can accelerate muscle recovery in athletes following high-intensity training.

Tea is also able to prevent cellular damage caused by oxidative stress, thus protecting muscles and tissues.

An animal experiment that was published in the journal “ Basic and Clinical Pharmacology and Toxicology ” showed that the use of epilgallocatechin gallate (EGCG) in mice with chronic fatigue syndrome promotes reducing markers of oxidative stress and exercise-induced inflammation.

What’s more, scientists say that by combining green tea with physical activity, you can increase energy and fat expenditure, increase endurance, and reduce the risk of muscle injury.

4. The best source of catechins for all diseases

Green tea is one of the richest sources of catechin antioxidants, according to work published by the Harvard Medical School in the United States.

Catechins are believed to be more effective than vitamins C and E when it comes to protecting cells from oxidative damage. Antioxidants such as catechins play a key role in maintaining health and fighting disease. Research shows they can protect against chronic diseases such as heart disease, diabetes and cancer.

Scientists also say that the concentration of these substances in matcha is higher than in any other type of tea.

In a study conducted by the University of Colorado in the United States, scientists found that “the concentration of EGCG in a match is 137 times higher than in China Green Tips and three times higher than in other varieties of green tea.

Beneficial features

5.High L-Theanine for a Clear Mind

Scientists believe that through the combination of L-theanine and caffeine, matcha calms and relieves anxiety.

L-theanine is an amino acid found in all teas made from camellia chinensis. By consuming matcha green tea, you can increase the level of L-theanine in the body and stimulate the alpha rhythm of the brain, which will help you to relax and stay alert at the same time.

L-theanine helps to increase the levels of dopamine and gamma-aminobutyric acid (GABA) in the brain, which relieve anxiety.

Given the conditions in which matcha leaves are grown, it can contain up to 5 times more L-theanine than any other green tea.

6. Reducing the risk of developing heart disease and hypertension

Some studies claim that because matcha is high in antioxidants and catechins, it can help improve heart health.

For example, one study involving 40,000 people showed that those who drink more than 5 cups of green tea daily reduced the risk of death from a heart attack or stroke compared with those who drink less than 1 cup of this drink a day.

Other studies have found that green tea can help lower cholesterol and blood pressure levels, thus preventing the development of heart disease.

7. Reducing the risk of developing type 2 diabetes

The best way to prevent type 2 diabetes is to make small adjustments to your diet and lifestyle. And, according to scientists, a match can help in this, too.

For example, one analysis published in the journal “ Annals of Internal Medicine ” found that consumption of green tea reduced the risk of developing diabetes, taking into account age, gender, body mass index and others. risk factors.

Another study from the American Journal of Clinical Nutrition states that green tea lowers blood sugar, making it easier to control. Green tea also helps to significantly lower insulin levels.

8. Detoxification of the body

The rich green color of the matcha is the result of its high chlorophyll content. Chlorophyll is a plant pigment that is responsible for the perception of light during photosynthesis, which produces energy.

Since matcha leaves are hidden from the sun during their growth, the concentration of this pigment in the drink is significantly higher compared to other types of tea.

In addition to giving tea such an extraordinary bright color, chlorophyll helps to remove harmful substances, toxins, chemicals and heavy metals from the body.

Choosing the best

Due to the growing popularity of matches, it is increasingly found in health food stores, tea shops and online stores.

However, not all matcha teas are created equal. Here are some tips for choosing a good tea:

• Pay attention to the composition, make sure that only matcha is present in the matcha tea.
• Choose organic, non-GMO products.
• The best for making real whipped tea is ceremonial matcha, while culinary matcha is more suitable for lattes, pastries and smoothies.
• You can come across a packaged match. But keep in mind that not whole tea leaves are used for its preparation.
• The quality and degree of clarity will certainly affect the price of the tea, so a relatively inexpensive matcha may not be very good.
• Chinese matcha is usually cheaper, but it may contain impurities and pesticides, unlike Japanese matcha.

Cooking method

The simplest and most popular way to consume matcha is tea.But its traditional cooking method is very unusual and unique.

Below we offer you the simplest method for the correct brewing of matches:

In addition to tea, matcha can be used to make ice cream, smoothies and pastries such as pies, brownies and biscuits.

Looking for more ideas? Try the following amazing and unusual recipes:

• Matcha Latte
• Mango smoothie with matches
• Energy Green Smoothie
• Matcha green tea pancakes

Risks and side effects

Many people wonder if matcha contains caffeine.We answer. One of the main differences between matcha and other green teas is the caffeine level.

There is more of it in the match, since the entire tea leaf is involved in the process of its production. And yet, there is significantly less caffeine in a match than in coffee, about 70 ml per cup.

Therefore, we do not recommend drinking matcha for people who are caffeine-sensitive. Although the tea is soothing and balanced thanks to L-theanine, it is worth keeping an eye on the amount and, if you have trouble sleeping, avoid drinking it in the evening.

Due to its caffeine content, matcha green tea should be avoided by children, pregnant and lactating women.

Be aware that eating matches on an empty stomach can lead to stomach pain and bowel upset. It is best to drink tea after meals, especially if you suffer from ulcers or acid reflux.

If you have iron deficiency anemia, it is important to remember that consumption of green tea can cause a decrease in the absorption of iron from food.

Unfortunately, there are often impurities in the match, and buying an organic product does not always guarantee their absence. However, in Japanese matcha tea, there are usually fewer of them than in Chinese. But in any case, it is best to limit yourself to one cup of this drink a day.

Matcha can interact with some types of medications, so if you are taking any medications or have any health problems, please consult your doctor before using this green drink.

Final conclusions

• What is matcha? Matcha is a concentrated green tea in powder form that is made from whole tea leaves.
• Due to the way it is prepared, matcha has a higher content of nutrients such as antioxidants and catechins compared to other varieties of green tea.
• What does matcha tea taste like? It has a strong, distinctive earthy flavor and is often compared to spinach or wheatgrass.
• Potential benefits of matches include improving heart health, helping weight loss, lowering blood sugar, detoxifying the body, and fighting anxiety.
• There are many ways to incorporate matcha into your diet and experience its benefits. In addition to tea, it can be used to bake, make smoothies and desserts, thus increasing the content of antioxidants in them.

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90,053 90,000 Brew, stir, sip – recent research confirms that tea is good for the heart

This month, special attention is paid to heart health. a cup of tea along with other healthy tips for cardiovascular health such as exercise, eating greens, and using olive oil in cooking.

Recent Published Studies Analyzed by Tea Advisory Group (www.teaadvisorypanel.com), confirm that tea’s rich polyphenol content really benefits your heart.

Commenting on these studies on behalf of Tea Advisory Group nutritionist Dr. Carrie Rexton noted, “In a large review of ^[1] , which combined 13 cohort and cross-sectional analyzes, 30 laboratory studies, and 13 clinical trials, regular tea consumption was associated with lower risk of cardiovascular disease. Laboratory and clinical trials have confirmed the protective effect of tea and its biologically active compounds against heart disease.

“This is confirmed by new research. ^[2] of over 100,000 7 Chinese adults followed for XNUMX years. Regular tea drinkers were 20% less likely to develop cardiovascular disease than those who did not drink tea. Traditional tea drinkers lived an average of 15 months longer and enjoyed an additional 17 months without any cardiovascular disease compared to non-tea drinkers. ”

General practitioner Dr. Jill Jenkins and TAP advisor adds: “ The ‘secret ingredient’ in tea is flavonoids According to a study published this year in Journal of Cardiovascular Pharmacology ^[3] , Flavonoids are part of the polyphenol family are natural compounds produced by the tea plant as it grows.Researchers have found that flavonoids improve the function of blood vessels, called “endothelial function,” by helping to control blood pressure. By doing this, foods rich in flavonoids such as tea, fruits and vegetables can help support cardiovascular health.

“Both black and green tea have similar effects on heart health, but differ in their actions. Study ^[4] found that a flavonoid present in green tea called epigallocatechin gallate (EGCG) not only acts as a powerful antioxidant, but also helps the blood vessels relax and reduces the stickiness of white blood cells – all factors that help prevent cardiovascular diseases.

Dr. Carrie Rexton adds: “And the benefits of tea go beyond heart health. Research in International Journal of Molecular Science ^[5] concluded that “tea exhibits various health functions such as antioxidant, anti-inflammatory, immunoregulatory, anti-tumor, cardiovascular protective, anti-diabetic, anti-obesity and hepatoprotective effects “.

National Heart Month empowers us to take better care of our hearts.Putting on the kettle is a good first step.

“With its rich flavonoid content – which explains the impressive clinical effects on blood pressure, endothelial function, inflammation and the reduction of oxidative stress – tea should be part of any diet for heart health. The best evidence is about four cups a day – regular black or green tea – which can also be a great way to moisturize.

“It can be difficult to navigate all the information we receive about heart health, from quitting smoking to taking extra exercise, drinking less alcohol and managing our weight.From a dietary perspective, the focus should be on plants, including fruits, vegetables, whole grains and tea, as they all contain valuable bioactives such as flavonoids and other polyphenols that can have positive effects on health and well-being. ”

Sources

^[1] Shi-yu S et al. (2019) Effects and mechanisms of tea and its biologically active compounds for the prevention and treatment of cardiovascular diseases: an updated review.Antioxidants 8 (6): 166.https: //doi.org/10.3390/antiox8060166

^[2] Wang H et al. (2020) Tea consumption and the risk of atherosclerotic cardiovascular disease and all-cause mortality: the China-PAR project. Eur J Prev Cardiol doi: 10.1177 / 2047487319894685. [Epub ahead of print].

^[3] Yamagata K. and Yamori Y. (2020) Suppression of endothelial dysfunction with dietary flavonoids and preventive effects against cardiovascular disease.J Cardiovasc Pharmacol 75: 1-9.

^[4] Yamagata K (2019) Protective effect of epigallocatechin gallate on endothelial disorders in atherosclerosis. J Cardiovasc Pharmacol. Doi: 10.1097 / FJC.0000000000000792. [Epubahead Print]

^[5] Tan G.Yu. et al. (2019) Health Functions and Associated Molecular Mechanisms of Tea Components: An Update Review. Int J Mol Sci 20 (24). PII: E6196.

90,000 Can I drink tea with milk?

Can you drink tea and coffee with milk or eat fruits with dairy products? This question is asked by every fifth person who comes to the appointment.

The idea that some foods cannot be eaten with others came to us from Ayurveda, the ancient Indian system of medicine. According to her, there are several types of incorrect combinations:

• the use of products with multidirectional effects on the body;
• interaction of substances with each other with the formation of toxic combinations for the body or simply unsuitable products for humans.

So can you drink tea with milk? On the one hand, it is advised to drink this drink for nursing mothers to increase the amount of milk, on the other hand, they write that the combination is harmful.Tea contains polyphenols, which are beneficial for the body and reduce the risk of cardiovascular disease and certain types of cancer. Milk, in turn, contains the protein casein, which can bind these nutrients and hinder their absorption.

But what about the British who like to drink strong black tea with milk? Scientists from the Research Institute in Scotland are also puzzled by this question. Tests have shown that after drinking black tea, the concentration of various polyphenols in the blood increases by 10-45% within 80 minutes, regardless of whether the study participants drank the tea with or without milk.

Another more controversial combination is the combination of dairy products with fruit or chocolate. Some tests have shown that such a combination can reduce the antioxidant effect of the latter by 30%. But at least 70% of antioxidants stay with us, and this is definitely healthier than drinking sweet yogurt from the store. Plus, chocolate milk is one of the best drinks for post-exercise recovery and muscle building. According to other tests, the joint use of fruits and dairy products helps to normalize the intestinal microflora, reduces the risk of osteoporosis and allows better control of blood sugar in patients with diabetes.

Do you drink tea or coffee with milk? Eating cottage cheese with fruits or milk smoothies?

Anna Turusheva , nutritionist, nutrition and weight correction specialist at SKA Medical Center.
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Dr. Wu Fu told what kind of tea women need to drink – Rossiyskaya Gazeta

One of the most popular drinks, without a doubt, is tea, whose homeland is China.

Tea drinking in China is a whole art. The Chinese have long recognized the key role of tea in everyday life, in the Celestial Empire there is a widespread saying “in everyday life one cannot do without firewood, rice, oil, salt, soy sauce, vinegar and tea.” From a culinary point of view, tea is a drink based on brewed and infused tea tree leaves. Green, red, flower, black and oolong tea are rightfully considered the classic varieties of this aromatic drink. According to ancient Chinese physicians, green tea has the most healing effect on the body, since after processing in the tea leaf, basically all its useful elements are preserved.According to scientific research, the amount of vitamins contained in green tea is 5-6 times more than in black and other types of tea.

Every cup of tea you drink ruins the pharmacist
(old Chinese proverb)

Today, there is a tendency among fashionable young Chinese women to consume a variety of flower teas. Indeed, flower tea is distinguished not only by its exquisite aroma, but also has a cosmetic effect, and more importantly, it is extremely beneficial to health.

Dr. Wu Fu, a practitioner in the homeland of tea, in the Chinese province of Fujian, has been studying the art of tea for many years. He cites the following advantages of flower tea: “In the composition of flower tea there is a lot of usefulness, this also applies to tea from magnolia, jasmine tea, tea from rose petals. These flower teas to varying degrees support the” heat “or yang energy in the body, which not enough for women. Flower teas are effective antioxidants, slow down the aging process. In addition, flower tea soothes, prevents fatigue, and removes toxins. “

Each of the flower teas is unique and unique in its own way

Depending on its composition, flower tea can have a tonic or relaxing effect. Various varieties of flower teas are recommended for the purpose of strengthening the immune system, preventing cardiovascular diseases, as well as improving the functioning of the organs involved in the process of digestion.

There can be a lot of varieties and varieties: jasmine tea, rose petal tea, rosehip tea, chamomile, lavender, mint tea, etc.It is based on green tea with fruit or floral additives. Flower tea is especially good in hot weather, it relieves general condition and quenches thirst.

Properties of flower teas

– Chamomile tea can be found in almost every home. Its very scent is soothing. This tea with a sweetish taste is useful for bronchitis, headaches, it also relieves stomach pains and swelling of the throat. Chamomile infusion is very useful as a general tonic during seasonal flu epidemics.Regular use of such a drink will cleanse the body of toxins and even promote weight loss.

– Jasmine tea is the most popular, rich in vitamins that have a positive effect on humans. In the morning, a fresh infusion can perfectly invigorate. In addition, jasmine tea removes toxins, promotes weight loss, improves eyesight, promotes digestion, and gives tone. Most importantly, this tea helps restore emotional balance.

– Peony flower tea has excellent sedative properties – it is indicated for increased anxiety, fear, muscle pain, spasms of the bronchi and blood vessels.Peony tea is recommended for patients suffering from atherosclerosis, shortness of breath, bronchial and cardiac asthma, as well as spasms of the bile ducts, stomach, in case of renal colic; it is also indicated for people who show signs of epilepsy.

– Lavender tea has a calming effect, this herb is very beneficial for the whole body. Lavender flowers help with indigestion, nausea, headaches, migraines, liver disease, intestinal bloating, lavender infusion will give strength.A decoction of flowers strengthens the cardiovascular system, has a choleretic effect, and normalizes digestion. Its aroma relaxes and relieves feelings of anxiety. Dried lavender flowers can be added to a hot bath to soak up and unwind after a busy day.

Dr. Wu Fu: “You should choose the kind of tea that will be useful for you.”

In China, almost everyone is well aware of the medicinal and prophylactic properties of the tea drink. Today, when we are all exposed to stress and heavy loads at work and in life, bad habits are increasingly making themselves felt: we smoke, abuse alcohol to relax, we do not sleep well or do not sleep at all at night.How can simple tea help in this case? In other words, how to drink tea correctly so that it shows its beneficial effect? Dr. Wu Fu clarifies:

You should choose the kind of tea that will be useful for you. For a full , I suggest drinking black tea and oolong tea, as these varieties help you lose weight. Skinny I would recommend drinking more green and flower tea . By the way, for smokers , I recommend to constantly drink green tea , since it helps to neutralize the effect of cigarette poison; For those who abuse alcohol , it is better to drink flower and black tea .In addition, children and adolescents are not recommended strong tea, they can rinse their mouth with tea, because tea has a hygienic effect. For women who have given birth, those who are engaged in physical labor, and those who work under the conditions of constant psychological pressure , I recommend black tea , as it restores and tones up. ”

Ripe tea leaves contain about 300 useful substances, including tannins, alkaloids, essential oils, proteins, carbohydrates, organic acids, minerals, trace elements, vitamins, etc.

Tea as medicine

– In case of inflammation of the eye , use a strong infusion of a mixture of green and black teas, to which add a teaspoon of dry wine: pour the cooled infusion into a cup or bowl, lower your head so that the eyeball touches the surface of the infusion, and open at least 10 times and close your eye. Then open your eye and rotate it with the eyeball to wash it with the infusion. Repeat this procedure several times.

– Green tea infusion relieves a cold .Pour a teaspoon of dry tea with a glass of boiling water, leave for 20 minutes, rinse your nose with warm infusion, freeing it from accumulated mucus. This procedure is repeated 6-8 times a day. At night, drip 4-5 drops of warm infusion into both nostrils. Gargle with a slightly warmed strong infusion of green tea for sore throat, laryngitis and pharyngitis, such gargling is excellent for ulcers and inflammatory processes in the oral cavity.

Why you need to drink green tea

The benefits of green tea can hardly be overestimated.It’s all about its composition, which has 500 chemical elements (magnesium, phosphorus, zinc, fluorine, etc.), 450 types of organic compounds and many vitamins (C, B, P). This is a real vitamin bomb.
The main components of green tea and what they are responsible for:

Caffeine (but not in pure form, but in theins) – invigorates and tones. Green tea, the properties of which are appreciated by all “larks”, when brewed correctly, invigorates just as much as coffee. Caffeine and antioxidants, which are abundant in green tea, help the body burn calories.Plus, the metabolism is accelerated, which contributes to weight loss. And if you reinforce the effect with intense training, the result will not be long in coming.
Minerals . The composition of green tea contains from 4 to 7% of micro- and macroelements, which is good. After all, the lack of even one mineral lowers immunity and negatively affects the general condition of the body. For example, a lack of zinc leads to hair loss and flaking nails.
Polyphenols . They help in the prevention of cardiovascular diseases.

Green Tea Experiments
Obesity affects 30% of the world’s population. In search of an effective weight loss remedy, British scientists have also investigated the beneficial properties of green tea. And here’s what came of it:
At the University of Edinburgh, Queen Margaret conducted a small experiment. Overweight students followed a strict diet and drank 4 cups of green tea a day. Within two weeks, the total cholesterol level dropped and the blood pressure returned to normal.
The University of Birmingham conducted a study that showed that after drinking green tea, fat is oxidized 17% faster than after taking a placebo.
In Central Asia, green tea is washed down with fatty foods to avoid a feeling of heaviness in the stomach.

Pressure decreasing
Is green tea good for blood pressure? Research has shown that it actually reduces blood pressure. However, the experiments were carried out on people with mildly high blood pressure.It is unlikely that tea will be able to cure chronic high blood pressure or prevent heart disease.

Stress Management
Theobromine and theophylline in the tea tone up the nervous system, relieve stress. In addition, L-theanine lowers the level of the “raging” hormone – cortisol. To increase your stress resistance to stressful situations, we recommend drinking green tea for 6 weeks. However, use weakly brewed tea in small portions, then the effect will be evident.

Beneficial properties for teeth
Green tea prevents tooth decay. In 2014, a small study was conducted at the National University of Chemistry in Ljubljana. Compared antibacterial mouthwash to green tea. They turned out to be equally effective. Only green tea is cheaper and tastier.

Avitaminosis is not terrible
Green tea holds the record for vitamin P, which strengthens the walls of blood vessels.There is also a lot of vitamin C in it: 10 times more than in black. A complex of B vitamins normalizes the nervous system, stimulates metabolism and improves skin condition. The body is cleansed of toxins

The complex composition of green tea protects against radiation sickness.
How does this concern you? If you work in front of a computer screen or like to sit in front of the TV, then urgently buy yourself 50 grams of green tea. Better than 100. It is a strong antioxidant, it contains a lot of tannins that cleanse the body of radioactive radiation.Tea can be drunk for various food poisoning for quick detoxification. It cleanses the kidneys of toxins and salts due to its diuretic function. Harmful substances are excreted even with sweat. At the same time, the pores are cleared, the skin breathes easier. Possesses strong bactericidal properties, successfully copes with food poisoning.

Long live healthy skin and hair
In the composition of Chinese cosmetics and even dietary supplements, you can find an unusual ingredient – green tea extract.