What is the relationship between calcium and vitamin D? How do they affect skeletal and extraskeletal health? Find the answers to these questions and more in this comprehensive article.

Understanding the Importance of Calcium and Vitamin D

Calcium and vitamin D are two essential nutrients that play a crucial role in maintaining overall health, particularly in the skeletal and extraskeletal systems. Vitamin D helps with the absorption of calcium, making it a vital component in the regulation of calcium homeostasis. This intricate relationship between calcium and vitamin D has been the subject of extensive research, with recent studies providing valuable insights into their impact on various aspects of human health.

Vitamin D Deficiency and Its Consequences

Vitamin D deficiency is a widespread issue, with a significant number of individuals worldwide exhibiting inadequate levels of this nutrient. A comprehensive review by Holick (2007) highlighted the prevalence and consequences of vitamin D deficiency, drawing attention to its association with a range of health concerns, including skeletal and extraskeletal complications.

Mechanisms of Vitamin D and Calcium Interactions

The interplay between vitamin D and calcium is complex and multifaceted. Recent studies have shed light on the underlying mechanisms that govern their relationship. For instance, Zhou et al. (2006) described the crosstalk between the steroid and xenobiotic receptor (SXR) and the vitamin D receptor (VDR), which mediates the expression of CYP24, a key enzyme involved in the catabolism of vitamin D. This discovery has important implications for understanding drug-induced osteomalacia, a condition characterized by impaired bone mineralization.

Age-Related Differences in Calcium Absorption

Calcium absorption is not a static process; it can be influenced by various factors, including age. Pattanaungkul et al. (2000) found that the relationship between intestinal calcium absorption and 1,25-dihydroxyvitamin D levels differs between young and elderly women, suggesting an age-related resistance to the action of 1,25(OH)2D in the intestine.

The Skeletal and Extraskeletal Benefits of Vitamin D and Calcium

The benefits of vitamin D and calcium supplementation extend beyond their impact on skeletal health. Amling et al. (1999) demonstrated that the skeletal phenotype of vitamin D receptor-ablated mice could be rescued in the setting of normal mineral ion homeostasis, highlighting the importance of vitamin D and calcium in maintaining overall skeletal integrity.

Vitamin D and Calcium Supplementation: Evidence-Based Recommendations

Numerous studies have investigated the effects of vitamin D and calcium supplementation on various health outcomes. Chapuy et al. (1992, 2002) reported the positive impact of combined calcium and vitamin D3 supplementation on the prevention of hip fractures in elderly women, while Trivedi et al. (2003) and Dawson-Hughes et al. (1997) found similar benefits in both men and women. These findings have contributed to the development of evidence-based recommendations for vitamin D and calcium supplementation in various age groups and populations.

The Prevalence of Vitamin D Insufficiency

Despite the recognized importance of vitamin D, studies have shown that a significant portion of the population exhibits vitamin D insufficiency. Chapuy et al. (1997) reported a high prevalence of vitamin D insufficiency in an adult normal population, while Thomas et al. (1998) and van der Wielen et al. (1995) observed similar patterns among medical inpatients and elderly people in Europe, respectively. These findings highlight the need for increased awareness and targeted interventions to address this widespread deficiency.

In summary, the interplay between calcium and vitamin D is crucial for maintaining both skeletal and extraskeletal health. Vitamin D deficiency can have far-reaching consequences, and understanding the underlying mechanisms and age-related differences in calcium absorption is essential for developing effective strategies to address this public health concern. The growing body of evidence on the benefits of vitamin D and calcium supplementation underscores the importance of ensuring adequate nutrient intake, particularly among vulnerable populations.

Calcium and Vitamin D: Skeletal and Extraskeletal Health

Papers of particular interest, published recently, have been highlighted as:

• Of importance

•• Of major importance

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Calcium/Vitamin D Requirements, Recommended Foods & Supplements

Calcium and vitamin D are essential to building strong, dense bones both when you’re young and as you age. The information included here will help you learn all about calcium and vitamin D – the two most important nutrients for bone health.

It is equally important to continue getting enough calcium and vitamin D to prevent further bone loss if you are prescribed a medication to prevent bone loss or fractures.

What is Calcium and What Does it Do?

A calcium-rich diet (including dairy, nuts, leafy greens and fish) helps to build and protect your bones.

Calcium is a mineral that is necessary for life. In addition to building bones and keeping them healthy, calcium enables our blood to clot, our muscles to contract, and our heart to beat. About 99% of the calcium in our bodies is in our bones and teeth.

Every day, we lose calcium through our skin, nails, hair, sweat, urine and feces. Our bodies cannot produce its own calcium. That’s why it’s important to get enough calcium from the food we eat. When we don’t get the calcium our body needs, it is taken from our bones. This imbalance causes bones get weak and easier to break.

Too many Americans fall short of getting the amount of calcium they need every day and that can lead to bone loss, low bone density and even broken bones.

How Much Calcium Do You Need?

The amount of calcium you need every day depends on your age and sex.

*This includes the total amount of calcium you get from food and supplements.

How Much Calcium Do You Eat?

Use the International Osteoporosis Foundation’s Calcium Calculator to find out.

Sources of Calcium

Calcium-Rich Food Sources

Food is the best source of calcium. Dairy products, such as milk, yogurt, and cheese are high in calcium. Certain green vegetables and other foods contain calcium in smaller amounts. Some juices, breakfast foods, soymilk, cereals, snacks, breads and bottled water have added calcium in fortified foods. If you consume soymilk, other nut based milks ( i.e.: almond or oat milk) or another liquid that is fortified with calcium, be sure to shake the container well as calcium can settle to the bottom.

A simple way to add calcium to many foods is to add a single tablespoon of nonfat powdered milk, which contains about 50 mg of calcium. It is easy to add a few tablespoons to almost any recipe.

Reading Food Labels – How Much Calcium Am I Getting?

To determine how much calcium is in a particular food, check the nutrition facts panel for the daily value (DV). Food labels list calcium as a percentage of the DV. This amount is based on 1,000 mg of calcium per day. For example:

• 30% DV of calcium equals 300 mg of calcium.
• 20% DV of calcium equals 200 mg of calcium.
• 15% DV of calcium equals 150 mg of calcium.

Calcium Supplements

The amount of calcium you need from a supplement depends on how much you get from food. Try to get the daily amount recommended from food and only supplement as needed to achieve the recommend daily allowance. In general, you shouldn’t take excess supplements that you don’t need. If you get enough calcium from foods, you may not need to take a supplement. There is no added benefit to taking more calcium than you need. Doing so may even carry some risks such as constipation, kidney stones and perhaps excess heart calcification.

Calcium supplements are available without a prescription in a wide range of preparations (including chewable tablets, gummy preparations, powders and liquid) and in varying amounts and sizes. The best supplement is the one that meets your needs for tolerability, convenience, cost, and availability. When choosing a supplement, keep the following in mind:

• Choose brand-name supplements with proven reliability. Look for labels that state “purified” or have the USP (United States Pharmacopeia) symbol. The “USP Verified Mark” on the supplement label means that the USP has tested and found the calcium supplement to meet its standards for purity and quality.
• Read the product label carefully to determine the amount of elemental calcium, which is the actual amount of calcium in the supplement, as well as how many doses or pills you have to take. When reading the label, pay close attention to the “amount per serving” and “serving size.”
• Calcium is absorbed best when taken in amounts of 500 – 600 mg or less. This is the case for both foods and supplements. Try to get your calcium-rich foods and/or supplements in small amounts throughout the day, preferably with a meal. While it’s not recommended, taking your calcium all at once is better than not taking it at all.
• Take (most) calcium supplements with food. Eating food produces stomach acid that helps your body absorb most calcium supplements. The one exception to the rule is calcium citrate, which can absorb well when taken with or without food.
• When starting a new calcium supplement, start with a smaller amount to better tolerate it. When switching supplements, try starting with 200-300 mg every day for a week, and drink an extra 6-8 ounces of water with it. Then gradually add more calcium each week.
• Side effects from calcium supplements, such as gas or constipation may occur or worsen. If increasing fluids in your diet and obtaining enough fiber does not solve the problem, try another type or brand of calcium. It may require trial and error to find the right supplement for you, but fortunately there are many choices.
• Talk with your healthcare provider or pharmacist about possible interactions between prescription or over-the-counter medications and calcium supplements.

What is Vitamin D and What Does it Do?

Vitamin D is a fat soluble vitamin and plays an important role in protecting your bones, both by helping your body absorb calcium and by supporting muscles needed to avoid falls. Children need vitamin D to build strong bones, and adults need it to keep their bones strong and healthy.

How Much Vitamin D Do You Need?

**According to the National Academy of Medicine and National Institutes of Health the safe upper limit of vitamin D is 4,000 IU per day for most adults. These recommendations are for the general healthy adult population.

Sources of Vitamin D

There are three ways to get vitamin D:

• Sunlight
• Food
• Supplements

Sunlight

Your skin makes vitamin D in reaction to sunlight and stores it in fat for later use. How much vitamin D your skin can produce depends on time of day, season, latitude, skin pigmentation, age, and other factors.

There are many reasons people do not have enough vitamin D. As we age, our skin loses its ability to generate vitamin D. People who live in cities or in institutional settings like nursing homes spend too little time outdoors. Even people who spend time outdoors often use sunscreen to prevent skin cancer. Sunscreen with an SPF as low as 8 reduces vitamin D production by 95 percent.

Vitamin D in Food

Vitamin D is found in very few foods. Sources include fatty fish like wild-caught mackerel, salmon, and tuna. Vitamin D is added to milk and other dairy products, orange juice, soymilk, and fortified cereals.

Check the food label to see if vitamin D has been added to a particular product. One eight-ounce serving of milk usually has 25% of the daily value (DV) of vitamin D. The DV is based on a total daily intake of 400 IU of vitamin D. So, a serving of milk with 25% of the DV of vitamin D contains 100 IU.

It is often difficult to get all the vitamin D you need from sunlight and food alone. Some people with underlying conditions may need to take vitamin D supplements to support bone health.

Vitamin D Supplements

Healthy adults with no vitamin D deficiency should be able to get adequate amounts of vitamin D from sunlight and by consuming a well-balanced diet. People with osteoporosis and low bone mass should discuss their vitamin D levels with their healthcare provider to ensure they are getting an optimal amount.

Before adding a vitamin D supplement, check to see if any of the other supplements, multivitamins, or medications you take contain vitamin D. Many calcium supplements also contain some vitamin D.

There are two types of vitamin D supplements. They are vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). Both types are good for bone health.

Vitamin D supplements can be taken with or without food and the full amount can be taken at one time. While your body needs vitamin D to absorb calcium, you do not need to take vitamin D at the same time as a calcium supplement. If you need help choosing a vitamin D supplement, ask your healthcare provider to recommend one.

Vitamin D Deficiency: Are You at Risk?

Vitamin D deficiency occurs when you are not getting the recommended level of vitamin D over time. Certain people are at higher risk for vitamin D deficiency, including:

• People who spend little time in the sun or those who regularly cover up when outdoors;
• People living in nursing homes or other institutions or who are homebound;
• People with certain medical conditions such as Celiac disease and inflammatory bowel disease;
• People taking medicines that affect vitamin D levels such as certain anti-seizure medicines;
• People with very dark skin;
• Obese or very overweight people; and
• Older adults with certain risk factors.

Talk to your healthcare provider if you have any of these risk factors. If you have osteoporosis, low bone mass or another medical condition that can lead to bone loss and also have a vitamin D deficiency, your healthcare provider may recommend vitamin D supplement to bring you up to a healthy 25-hydroxy vitamin D level which is generally agreed upon by medical societies to be between 30-60 ng/ml.

A Guide to Calcium-Rich Foods

We all know that milk is a great source of calcium, but you may be surprised by all the different foods you can work into your diet to reach your daily recommended amount of calcium. Use the guide below to get ideas of additional calcium-rich foods to add to your weekly shopping list.

*The calcium content listed for most foods is estimated and can vary due to multiple factors. Check the food label to determine how much calcium is in a particular product.

Resources

–Show More +

• Calcium and Vitamin D Supplement Safety Fact Sheet
• Just the Facts: Latest Evidence-Based Research on Calcium from the National Institutes of Health (NIH) Office of Dietary Supplements (ODS)

Last Reviewed 5/23/2023

Do I need to take K2 with D3?

• May 18, 2021
• Author: Anna Fedortsova

Vitamins D and K are fat-soluble nutrients that play an important role in calcium metabolism in the body.

Vitamin D does this in two ways:

• improves the absorption of calcium from food
• pumps calcium from the bones into the blood. When you don’t get enough calcium from food, vitamin D maintains calcium levels in your blood. There it is more important, because it helps the heart to beat, the lungs to work, the cells to perform their task.

D-deficiency can lead to bone loss.

Vitamin K is essential for blood clotting and promotes the accumulation of calcium in bones and teeth. It activates the protein osteocalcin, which helps calcium get into the bones. And a special GLA protein (MGP) to collect excess calcium and prevent its accumulation in soft tissues, such as the kidneys, and blood vessels.

Is vitamin D harmful without vitamin K?

Perhaps if you overdo it with the dosage or regimen of vitamin D.

Excess D can lead to high levels of calcium in the blood (hypercalcemia). Calcium and phosphorus become so high that calcium phosphate begins to accumulate in the lining of the blood vessels. Vitamin K can help prevent this.

Does vitamin K help vitamin D work?

Rather yes than no. If calcium intake is insufficient and there is a vitamin D intake, then vitamin K can help slow the pumping of calcium from the bones into the blood.

Unanswered questions:

• In 2007, a nutritionist suggested that high doses of vitamin D could deplete vitamin K stores, potentially causing deficiency. While there is no confirmation or refutation
• It is not known if moderate and low doses of vitamin D are harmful in the long term for vitamin K deficiency
• How much vitamin K is needed for high doses of vitamin D. The current daily allowance for vitamin K is based on the liver’s requirement for clotting factor synthesis. We did not find calculations for bones and vessels
• Which form of vitamin K is needed to stabilize calcium levels: menaquinone (K2) or phylloquinone (K1)? Research is still underway, until it was decided that K2. Thank you for eliminating menadione (K3).

The European Food Safety Authority has confirmed the benefits of vitamin K: “a causal relationship has been established between dietary intake of vitamin K and the maintenance of normal bones.” The US Food and Drug Administration has the opposite view.

What do we think?

In each individual case, you need to decide personally with the endocrinologist. Without analyzes and evaluation of the diet – it can be dangerous.

What vitamin ensures the absorption of calcium in the body

THERE ARE CONTRAINDICATIONS. SPECIALIST CONSULTATION IS REQUIREDVitamin DB group vitaminsCalciumMagnesiumZinc

Contents of the article

• What effect does calcium have on the human body?
• What vitamin ensures the absorption of calcium in the body?
• What foods are best for calcium absorption
• What foods flush calcium out of the body
• Sources

Calcium (Ca) is one of the few elements that is needed by almost every cell. Without it, the full formation of tissues and the normal course of biochemical processes are impossible. The body cannot synthesize Ca on its own. Food and special additives provide its replenishment.

But in order to replenish the reserves, it is not enough to receive the necessary doses of the microelement. You also need to create conditions for its assimilation. A number of useful substances contribute to this process. What vitamin ensures the absorption of calcium and what is the role of this nutrient?

What effect does calcium have on the human body?

The distribution of Ca in the body is uneven – 99% of the element is contained in the teeth and bones, and only 1% is distributed to other organs. The substance comes in from the outside, and its excretion is provided by the kidneys and intestines.

Functions performed by Ca:

• Balances the processes of excitation and inhibition in the cerebral cortex
• Necessary for bone formation and mineralization of teeth
• Affects the heart rhythm and blood clotting
• Participates in the formation of many hormones and enzymes;
• Helps to strengthen the immune system

The substance provides bone strength. At the same time, bone tissue acts as a kind of depot for its storage. With a deficiency of an element, the body begins to use these reserves. Prolonged removal of the mineral from the bones leads to osteoporosis, deterioration of the central nervous system (CNS) and heart, tooth decay, and the development of allergic reactions.

In a child’s body, calcium deficiency is manifested by metabolic disorders, pathological formation of the musculoskeletal system and teeth, and poor sleep.

The mineral requirement depends on age. In addition, gender, lifestyle, and the presence of diseases matter. Large doses of the nutrient (up to 1500 mg) are necessary for women during pregnancy, breastfeeding, postmenopausal women.

However, an excess of the substance can also lead to health problems. The use of more than 2.5 mg of calcium per day causes a deterioration in appetite, constipation, increased blood pressure (BP), convulsions, and increases the risk of calculus formation. Therefore, the mineral should enter the body only in the required quantities. And for its full assimilation, it is necessary to take preparations additionally enriched with other vitamins and microelements.

Which vitamin ensures the absorption of calcium in the body?

Ca absorption is a complex process, for which vitamin D is primarily important. It improves the absorption of the mineral in the small intestine and helps strengthen bones. With a lack of vitamin, calcium can be poorly absorbed even when taken in the right quantities.

Additionally, vitamins act as a support group:

• C – accelerates the maturation of collagen, which acts as a natural support for bone tissue, skin, blood vessels. Protects blood vessels and the heart, prevents the development of allergies.
• B6 – improves the absorption of magnesium, necessary for the full functioning of the central nervous system.
• K1 – prevents osteoporosis. Together with vitamin D, it is involved in the synthesis of osteocalcin, which helps to retain calcium. Reduces the risk of fractures.

Minerals are also needed for better absorption of Ca: magnesium (Mg), phosphorus (P), zinc (Zn), iodine (I).

Fully provide the body’s need for calcium and its maximum assimilation of such combined preparations as Calcium D-3 Nikomid-Forte, Calcemin, Osteogenon. But you can take them only as prescribed by a doctor. In the absence of the opportunity to consult with a specialist, stocks can be replenished with food.

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From what foods calcium is best absorbed

Many foods are rich in calcium. To replenish the body with the mineral, you need to include in the diet:

• Sesame seeds – most Ca contains seed coats, so you need to use unpeeled seeds. Peeled sesame seeds practically do not bring benefits.
• Milk and dairy products – the element is best absorbed from pasteurized milk. UHT and sterilized dairy products contain much fewer substances that help good absorption of Ca.
• Greens, vegetables, nuts, berries and fruits – compared to milk, they have less calcium. The element is best absorbed from raw vegetables and fruits.

Combining these products, you can provide the body with the necessary amount of the substance. However, Ca is easily washed out. Therefore, it is necessary not only to saturate the body with a mineral, but also to prevent its leaching.

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contribute to its leaching from the bone tissue. These include:

• Palm oil – prevents the absorption of calcium and many useful substances.
• Coffee – flushes Ca and other minerals from the body. No more than 4 cups of coffee with a capacity of 30 ml are allowed per day.
• Sweets – disrupt the intestinal microflora, in which all useful substances are absorbed.