Where to look for vitamin D and what to do to ensure it is best absorbed. Vitamin D - biological functions, intake rates, symptoms of deficiency and excess

Hello, dear friends!
Everyone knows that there is a whole group of B vitamins. However, the same can be said about vitamin D. In this article I will tell you not only what foods (plant and animal origin) contain a lot of vitamin D, but also how to eat properly so that the beneficial nutrient is fully absorbed .

The relationship of this vitamin with calcium and ultraviolet radiation

As a child, many of us were told by our mother, “Eat cottage cheese, you need a lot of calcium.” Meanwhile, if there is a deficiency of vitamin D in the body, no matter how much cottage cheese (yogurt, milk, etc.) you buy, calcium will leave the body without being absorbed. And this is bad, because if there is a lack of this nutrient in the blood, bone tissue will begin to deteriorate - the body will simply “steal” the calcium it needs from there. And in this case, acidosis develops (increased acidity of the body), which affects the nervous system.

In general, it is not enough to know which foods contain more calcium - you need to add more of everything rich in vitamin D to your diet.

By the way, it does not always enter our body with food. Sometimes it’s enough to spend a little time under the sun or a quartz lamp, and then our own skin begins to produce vitamin D. Moreover the lighter its shade, the more useful nutrients it can give us. So in the summer you can sunbathe for hours, but do not give up the products from the list (you will see it below), which contain a lot of this vitamin, because dark, tanned skin will hardly produce it. But in winter or early spring, just 15 minutes in the solarium will be a real salvation for teeth and bones.

NB! Of the entire “family” of these vitamins, our body needs D2 and D3 the most. It is interesting that this group even has a name that is consonant with the nutrient with which it was created to create a pair - calciferols.

Sources of Vitamin D

In modern pharmacies there are many vitamin complexes or preparations containing only one vitamin (say, D3). You can even buy special vitamins for vegetarians, for the sake of which not a single cod or salmon died. However, it is much better (and tastier) to figure out which foods contain this nutrient and fill our refrigerator with them more often.

This table will tell you which products contain this important “family” in maximum quantities:

You may be a little confused by the mysterious “ME” next to the vitamin content numbers. These letters stand for "action units".

NB! One IU is equal to 0.025 mg of vitamin D in its pure form.

But it’s not enough to hang this table on the wall in the kitchen and constantly look at which foods contain the most vitamin D - if its “supply” to the body is too high, that’s also bad. So it’s better to calculate the daily requirement of this vitamin:

adults: 100 IU or 2.5 mcg per day (interestingly, foreign doctors recommend that their patients consume even more - up to 400 IU);
pregnant women and constantly growing children: 400-500 IU or 10 mcg per day.

Sometimes parents try so hard to take care of their children that they not only stuff them with extra vitamins, but also put them under an ultraviolet lamp. But When the body receives more than 50 IU of calciferols per day, the beneficial vitamin becomes a toxin. Of course, to achieve this, it’s not enough to just eat fish or liver every day - but extra pharmaceutical complexes (especially if they are “prescribed” not by a doctor, but by a mother after watching an advertisement or for other reasons) may well cause harm.

This has already happened if your child:

poor appetite, vomiting, and even nausea;
constipation;
drowsiness, apathy, loss of strength;
calmness gives way to excitement, convulsions may appear;
sudden weight loss;
headache.

How and when can you use these foods beneficially?

When planning your diet, you need to make adjustments for the season.

Autumn (even sunny - the whole body is still hidden under clothes), winter, spring: you can not only buy canned cod liver, ghee or mushrooms, but also “indulge” in vitamin complexes. For example, with cholecalciferol D3. They will not only help to avoid bone tissue diseases, but will also support the immunity of both adults and children, not only in “sterile” home conditions, but also when visiting kindergarten or school.

By the way, this picture can serve as a cheat sheet for you to successfully combine foods rich in calcium and vitamin D. Of course, drinking herring with milk is a pleasure only for extreme sports enthusiasts, but if you bake it with cheese, sprinkled with sesame seeds, you will get a very sophisticated dinner.

Summer, as well as May: in 30 minutes spent outside, our body kindly produces 600 IU of calciferols. So there is no need to spend money on salmon or tuna - just take sunbathing regularly.

But do not think that in the summer everyone receives ultraviolet radiation in the same amount. City dwellers often experience a deficiency of it! Judge for yourself: a short dash to a bus or car, then 8 hours in the office, and again transport. The windows almost do not allow ultraviolet radiation to pass through, and city smog acts as an “ultraviolet filter”... Therefore, only hardcore, only frequent walks in the park! Well, or at least get off one stop early and walk along the sidewalk. By the way, this is also useful for muscles and figure.

NB! Did you know that calciferols are contained in the outermost layer of the skin - a secretion that is terribly afraid of soap, as it is removed from the skin when washing hands? So too frequent hygiene procedures also do not contribute to the accumulation of vitamin D in our body.

Vegetarianism: what to put on the menu?

Vitamin D is most often found in dairy products or fish. But what if you are a vegetarian, or even a vegan? Pay attention to:

cocoa: it contains 6.6 mcg of calciferols per 100 g of powder;
morel and chanterelle mushrooms: 100 g of product contains a little more than 5 mcg (fresh product is stored in the refrigerator for a maximum of a day or two, it is advisable to keep canned product in the basement or the same refrigerator);
oyster mushrooms: 0.7 mcg per 100 g;
Shiitake mushrooms: 0.32 mg per 100 g; are sold both fresh and dried - in the second case they are even considered healthier (they can be stored in the pantry, in a tightly closed jar);
porcini mushrooms: 0.2 mcg;
soy milk: 0.13 mg per cup - refrigerated for up to a week;
champignons: 0.1 mcg;
carrot and lemon juice: 0.1 mcg;
greens (dill, parsley), as well as sprouted wheat: 0.1 mcg.

As for pharmaceutical complexes, it is recommended to keep them in a cool, dry place. The main thing is that moisture and direct sunlight do not get into the cabinet (therefore it should not have a glass door... well, or the jar of vitamins should be opaque). Some manufacturers recommend putting bottles in the refrigerator (however, this often applies to non-vegetarian vitamins - the same as fish oil).

Why does a person need vitamin D?

Calciferol deficiency in the body can be guessed by the following symptoms:

weakened muscles,
problems with ligaments, bones and teeth (even banal caries), swollen and aching joints,
impaired heart tone,
increased malfunctions of the kidneys, liver,
brittle, split ends,
it is unclear where myopia came from (especially since you do not work with a computer or books),
poor memory, constant depressive thoughts (yes, a deficiency of this vitamin is very exhausting to our nervous system, which can also “come back to haunt” insomnia, painful excitability, and general nervousness),
you constantly catch colds, your immunity is below par.

the fontanel takes a long time to heal,
rickets develops, the bones become deformed (for example, you can see the curvature of the legs),
teeth do not erupt for a long time,
severe sweating appears,
poor appetite
sleep disorders.

It's early spring, the sun is lazy, and we still haven't put away our winter jackets. It is not difficult to guess that the amount of cholecalciferol in our body is extremely low. “Fish days” in the diet, solarium or pharmaceutical capsules (for example, fish oil)? The choice is yours. But no matter what you choose, your body (and especially your skeleton) will thank you very much!

Low vitamin D intake is considered a major public health problem worldwide. In fact, vitamin D deficiency is estimated to affect 13% of the world's population ().

Here are 7 effective ways to get vitamin D.

What is vitamin D?

Vitamin D is a fat-soluble vitamin that primarily aids in the absorption of calcium and promotes the growth and mineralization of your bones. It is also involved in various functions of your immune, digestive, circulatory and nervous systems ().

New research shows it may help prevent various diseases and conditions such as depression, diabetes, cancer and heart disease. However, the relationship between vitamin D and these diseases is still poorly understood ().

How much vitamin D does your body need?

There is considerable debate in the scientific community about how much vitamin D the human body needs.

While National Academy of Medicine believes that 600–800 IU of vitamin D per day is sufficient for the majority of the population, Endocrine Society recommends 1500–2000 IU per day (,).

The optimal level of vitamin D in the blood has not been established, but it is likely to be between 20 and 50 ng/mL ( , , ).

National Academy of Medicine also suggests that daily intake of up to 4,000 IU of vitamin D per day is safe for most people, although much higher doses may be temporarily needed to increase blood levels in some people ().

Although toxicity is rare, it is best to avoid long-term doses of vitamin D greater than 4,000 IU without the supervision of a qualified professional.

Summary:

Vitamin D is essential for calcium absorption and bone health. Although there are no set guidelines, dosage recommendations range from 600 to 2,000 IU per day, but some people may require higher doses to achieve and maintain healthy blood levels.

1. Spend time in the sun

Vitamin D is often called the "sunshine vitamin" because the sun is one of the best sources of this nutrient.

Your skin contains a type of cholesterol that functions as a precursor to vitamin D. When this compound is exposed to ultraviolet radiation from the sun, it becomes vitamin D.

In fact, sun-derived vitamin D can last twice as long as vitamin D from food or supplements ().

However, the amount of vitamin D your body can produce depends on several variables.

Skin color and age

People with darker skin need to spend more time in the sun to produce vitamin D than people with lighter skin. This is because dark skin contains more melanin, a compound that can inhibit the production of vitamin D ().

Age may also have an impact. As you get older, your skin's production of vitamin D becomes less efficient ().

Geographical location and time of year

The closer you live to the equator, the more vitamin D you will be able to produce year-round due to your physical proximity to the sun's rays.

Conversely, your opportunities for adequate sun exposure decrease in proportion to your distance from the equator ().

Sunscreen and clothing

Certain types of clothing and sunscreen can interfere with—if not completely block—vitamin D production ().

While it is critical to protect yourself from skin cancer by avoiding overexposure to the sun, your body requires very little unprotected sun exposure to begin producing vitamin D.

Although there are no official recommendations, sources suggest that for people with fair skin, just 8-15 minutes of sun exposure is enough to get plenty of vitamin D. People with dark skin may need more time ().

Summary:

Your skin can produce large amounts of vitamin D on its own when exposed to sunlight. However, many factors influence this process.

2. Consume oily fish and seafood

Here are other types of fish and seafood that are rich in vitamin D:

oysters
anchovies

Summary:

Fatty fish and seafood are among the foods highest in vitamin D, although the exact vitamin content may vary depending on the type and source of the food in question.

3. Eat more mushrooms

Mushrooms are the only completely plant-based source of vitamin D.

Like humans, mushrooms can produce their own vitamin D when exposed to ultraviolet light. Humans produce a form of vitamin D known as D3 or cholecalciferol, while fungi produce D2 or ergocalciferol ().

Both forms of this vitamin can increase circulating levels of vitamin D in the blood, although research suggests that D3 may increase levels more effectively and efficiently than D2 ().

While vitamin D content varies depending on the type of mushroom, some varieties, such as wild maitake mushrooms, provide up to 2,348 IU per 100-gram serving. This is almost 300% of the RDI (,).

Due to exposure to sunlight, wild mushrooms typically contain more vitamin D than cultivated varieties. However, you can also purchase mushrooms that have been treated with UV light.

However, you should always carefully identify mushrooms or purchase them from a reputable seller—such as a grocery store or farmers' market—to avoid exposure to poisonous mushroom species.

Summary:

Like humans, mushrooms produce vitamin D when exposed to ultraviolet light. Wild mushrooms—or commercially grown ones treated with ultraviolet light—have the highest levels of vitamin D.

4. Include egg yolks in your diet

Egg yolks are another source of vitamin D that you can easily add to your diet.

Like many other natural food sources, yolks have varying levels of vitamin D.

Conventionally raised chickens that do not have access to the outdoors typically only produce eggs at 2–5% of the RDI ().

However, some studies show that eggs from pasture-raised or free-range chickens produce up to 4 times more - or up to 20% of the RDI - depending on how much time the birds spend outside the home ().

Chicken feed can also affect the vitamin D content of eggs. Those fed vitamin D-fortified grains can produce yolks that may contain more than 100% of the RDI ().

Summary:

Backyard chicken eggs are an excellent source of vitamin D, as chickens with access to sunlight produce more vitamin D in their eggs than those left indoors.

5. Eat fortified foods

Because few foods contain large amounts of vitamin D, the nutrient is often added to staple foods in a process known as fortification.

However, you should keep in mind that the availability of vitamin D fortified foods varies by country, and the amount of vitamin D added to foods may vary depending on the brand and type of product.

Here are some foods that can be fortified with vitamin D:

cow's milk
plant-based milk alternatives such as soy, almond and hemp milk
Orange juice
ready-to-eat cereals
certain types of yogurt

If you are unsure whether a particular product has been fortified with vitamin D, check its ingredient list.

Summary:

To increase vitamin D intake, it is often added to staple foods such as milk and breakfast cereals.

6. Take Supplements

For many people, taking a vitamin D supplement may be the best way to ensure adequate intake.

Vitamin D exists in two main biological forms -. Typically, D2 comes from plants and D3 comes from animals ().

Research shows that D3 may be significantly more effective at absorbing and maintaining overall vitamin D levels than D2, so look for supplements with this form ().

Additionally, it is important to purchase high-quality supplements that have been independently tested. Some countries, such as the United States, do not regulate dietary supplements, which can negatively impact the quality of dietary supplements.

It's best to choose supplements that have been tested for purity and quality by a third party, e.g. U.S. Pharmacopeia (USP), Informed-Choice, ConsumerLab.com or Banned Substances Control Group (BSCG).

Dosage

Vitamin D supplements vary in dosage. However, the amount you need depends on your current vitamin D level.

For most people, 1000–4000 IU is considered a safe daily dose to maintain healthy levels ().

However, you may need a much higher dose in certain circumstances - especially if your current levels are very low or you have limited exposure to sunlight ().

For this reason, it is ideal to have your vitamin D levels checked by your doctor to ensure you are taking the most appropriate dose.

Vegan Supplements

Most vitamin D supplements are derived from animal sources and are therefore not suitable for vegans. However, there are several options for vegan vitamin D supplements.

Because vitamin D2 is plant-based, D2 supplements are generally beneficial for vegans and are widely available.

Vegan D3 is significantly less common than D2, but can be made from lichens. You'll likely find them in specialty health stores or online.

Summary:

If you don't get enough vitamin D from food or sunlight, supplementation may be helpful. Checking your vitamin D blood levels before taking supplements is the best way to find the right dose.

7. Try an ultraviolet lamp

Lamps that emit ultraviolet light can also increase vitamin D levels, although these lamps can be expensive.

When your skin is exposed to ultraviolet B (UVB) radiation from the sun, it can produce its own vitamin D. UV lamps mimic the effects of the sun and can be especially helpful if your sun exposure is limited by geographic location or indoors.

Ultraviolet light has been used therapeutically for a variety of skin conditions for decades, but only recently has it been recommended as a means to boost vitamin D levels ().

The safety of these devices is an important issue, as too much exposure can burn your skin. As a general rule, you are advised to limit your exposure to no more than 15 minutes at a time.

Summary:

You can purchase lamps that emit ultraviolet B light to stimulate the production of vitamin D. However, they can be expensive and dangerous if used for more than 15 minutes at a time.

Summarize

Vitamin D is an essential nutrient that many people around the world do not get enough of.
However, you can increase your vitamin D levels by getting more sunlight, eating foods rich in vitamin D, and/or taking supplements.
If you suspect you are low in this important nutrient, consult your doctor to have your levels checked.

Alexander Gushchin

I can’t vouch for the taste, but it will be hot :)

Content

Some people have been familiar with the taste of fish oil since early childhood, because... In childhood, vitamin D (Cholecalciferol) is very necessary for the normal development of the body. The lack of this important substance negatively affects the condition of human bones, skin, teeth, and hair. But not only fish oil contains D3. There are other foods rich in cholecalciferol. Find out what dishes and foods containing vitamin D are present in your diet. This guide will help you figure it out.

What foods contain large amounts of vitamin D?

Vitamin D is especially beneficial for the health of people of any age. This substance affects the exchange of calcium and phosphorus and their normal absorption. Small children born in autumn and winter are additionally prescribed artificial D3 to strengthen bone tissue. Cholecalciferol has a beneficial effect on strengthening the immune system; its intake helps prevent colds. The daily dose of D3 is 2.5 mcg, which the body must obtain from food.

The undisputed record holder for vitamin D content is fish oil. Per 100 g of this product there is more than 0.20 mg of vitamin, which is almost 20 times the human daily requirement. But it’s not only with the help of fish oil that you can replenish your reserves of nutrients. Thus, the source of D3 is considered to be sea fish, especially halibut, cod, and herring. Dishes made from them contain approximately 3 mcg of D3 per 100 g.

Fermented milk products: cheese, cottage cheese help to replenish cholecalciferol reserves well. It is useful to consume butter and vegetable oil, raw egg yolks. Nutritionists also advise diversifying your diet with fish liver, for example, cod, which contains the maximum concentration of D3 per 100 g. The body will also receive cholecalciferol from milk, but in a minimal amount, since the fresh product contains phosphorus, which prevents its normal absorption.

Oatmeal, parsley, potatoes, dandelion greens, and horsetail can satisfy the body's need for cholecalciferol. But plant foods contain very little vitamin D, so among vegetarians there are frequent cases of illness due to its deficiency. Thus, children with D3 deficiency suffer from rickets, and adults develop osteoporosis. An insufficient amount of this substance is manifested by increased fatigue, drowsiness and lethargy.

In the human body, vitamin D can be produced through sunbathing. The substance is synthesized under the sun's rays, so summer walks in the sun are good for health. But the main thing is moderation. No doctor will recommend sunbathing for several hours to get your daily dose of D3. It is recommended to stay in the sun for no more than a quarter of an hour and only in the morning and evening (before 10 am and after 5 pm), when the sun is less aggressive, and not in the active phase.

List of foods that supply calcium and vitamin D3

Once in the body, vitamin D3 will also act as a regulator of calcium and phosphorus levels, helping their absorption to strengthen bone tissue. It is advisable to include in the menu dishes that contain both D3 and calcium. You can use to prepare them:

kefir;
sour cream;
fatty varieties of sea fish;
natural yogurt;
eggs;
cottage cheese;
goat and sheep milk;
pork and beef liver;
chicken liver;
tuna;
butter;
mackerel;
herring.

In addition to dishes containing calcium, ultraviolet rays are needed to saturate the body with D3. Moderate exposure to the sun on human skin has a beneficial effect on health and well-being. Doctors have proven that at least 90% of the total amount of vitamin D in the body is synthesized by the skin under the influence of ultraviolet radiation. When choosing places to sunbathe, give preference to beaches with clean air. Ultraviolet radiation does not pass through polluted air well, so there will be little benefit from taking such sunbathing. Find out in more detail which ones should be consumed if there is a shortage of it.

If you decide to compensate for the lack of D3 by taking synthesized drugs, be sure to consult your doctor. Sometimes taking foods and tablets artificially enriched with cholecalciferol causes the deposition of calcium salts. Therefore, such drugs are taken only for medical indications. About (in products and pharmaceuticals) for children's health, watch the video with Dr. Komarovsky.

Table of vitamin D content in food

Thanks to this table, you will be able to fill your diet with the right foods in order to receive an adequate daily dose of vitamin D and not face problems that occur due to its absence in our body.

For every minute spent in the sun during the daytime peak of its activity, the human body can produce about 1000 IU of vitamin D. Food contains much less of this “sun” vitamin. For comparison, to get the same amount of vitamin D, you need to drink 8-10 glasses of fortified milk. Thus, the sun is the best source of vitamin D. What is this vitamin for? First of all, for the best absorption of calcium by the bones. Doctors know that it is insufficient calcium in the bones that leads to the “silent epidemic of the century” - osteoporosis.

To get the magic vitamin from the sun without harm to your health, you need to take some precautions, because... Solar radiation can bring not only benefits, but also harm. So, here are simple rules to help you get vitamin D without getting hurt:

Time spent in the sun should be strictly limited. For people with very fair skin, it is enough to expose their arms and legs to the sun for 5-10 minutes to get the required portion of vitamin D. For such sunbathing, there is no need to apply protective products to the skin that block UV rays, since these drugs do not allow the skin to produce vitamin D. Short-term exposure to the sun is necessary from 10 am to 3 pm - it is during these hours that the highest peak of sun activity is observed. It is enough to sunbathe only 3 times a week. For people with darker skin, you can stay in the sun for 15-20 minutes, but if you are naturally dark-skinned, then increase your exposure to the sun to half an hour. Before sunbathing, do not forget to apply a cream with a protection factor of at least SPF 30 to your skin. Put a wide-brimmed hat on your head.
Save time - sunbathe while walking or shopping. In other words, you don't need to go to the beach to get vitamin D. In the city, in the country or in the park, exactly the same sun shines.
Be carefull. You can sunbathe only if you have no contraindications to being in the sun. For example, if one of your relatives suffered from skin cancer, it is better to consult a doctor before starting “sun therapy”. Some metabolic, skin, cardiovascular and immune system diseases also prevent sun exposure. If you have any chronic health conditions, talk to your doctor about the safety of sun treatments.

Do you live in northern latitudes or cannot get vitamin D from the sun due to contraindications to radiation? Then try to introduce more foods containing vitamin D into your diet.

What foods are rich in vitamin D?

Before you try to get vitamin D from food, you need to know your daily requirement. Thus, the National Osteoporosis Foundation (USA) recommends that adults take 400 to 800 IU of vitamin D per day. In old age, the rate of consumption of the sun vitamin increases to 800-1000 IU per day. However, many experts believe that most of us need even more vitamin D—up to 2,000 IU per day. This dose is needed to better resist diseases.

So, the daily norm is known. Now it is advisable to do a test for the level of “25-hydroxyvitamin D” in the blood serum. The normal level of “25-hydroxyvitamin D” in the blood is 40-60 ng/ml.
If the study shows that you do not have enough vitamin D, then it is worth taking measures to adjust your diet. Introduce foods containing natural vitamin D into your diet, as... it is absorbed by the body better than that obtained artificially. These products include fatty fish - salmon (360 IU per 100 g), sardines (250 IU), tuna (200 IU). It is necessary to have a fish lunch or dinner at least several times a week.

In addition, the food industry produces products already fortified with vitamin D. Look for information about the increased content of this vitamin on the labels. For example, it is added to milk, orange and other fruit juices (up to 100 IU per 100 ml), cereal products, yoghurts, soy milk (200 IU per 100 g).

If you cannot get the required amount of vitamin from food, then take vitamin supplements; most multivitamins contain up to 400 IU of vitamin D per dose. There are also specialized preparations for the best prevention and treatment of osteoporosis; they contain calcium and vitamin D in amounts of up to 1000 IU per 1 capsule.

Remember that even a short stay in the sun for 5-10 minutes can give you the necessary dose of vitamin D, so do not deny yourself walks in the fresh air, having first protected your head and face from direct sunlight.

Itamin D is perhaps the most discussed substance in both medicine and nutrition. The need for sufficient consumption arises in a person even before birth, because if the expectant mother experiences a deficiency of vitamin D, the newborn may subsequently have serious health problems. And in adult life, this substance cannot be replaced by any synthetic additives or pills. Of course, the modern pharmaceutical market offers tablet forms of a vitamin analogue, however, its properties, metabolism, and functions are significantly inferior to natural ones, not to mention possible side effects, allergic reactions, overdoses and other complications. Therefore, natural sources of vitamin D are a must in the daily diet of everyone who strives to maintain their health for many years. Where does this substance necessary for the normal functioning of the body come from, how is it absorbed and what functions does it perform? First things first!

Vitamin D: name and properties

Vitamin D is not one, but a whole group of substances similar in structure, function and biological activity. This list includes:

Ergocalciferol, or form D 2. This vitamin was first isolated from yeast.
Ergosterol, provitamin D 2 - can be found in extracted forms of yeast-like forms, molds, etc.
Cholecalciferol, or form D 3. Perhaps the most common form of vitamin D. It is synthesized in the tissues of living organisms (including, of course, humans) under the influence of the ultraviolet spectrum of sunlight.
22, 23-dihydroergocalciferol, or form D4.
Sitocalciferol, or form D 5. This vitamin is also known as 24-ethylcholecalciferol, isolated from wheat oil extract.
Stigma-calciferol, or form D. Scientific name “22-dihydroethylcalciferol”.

In medicine, vitamin D has a general name - “calciferols”. However, this term most often refers to two forms of this vitamin - D 2 and D 3. Despite the variety of forms, it is these two varieties that are of particular importance to humans. If the first enters the human body from the outside, that is, with food, and only after that is absorbed in the intestines and enters the blood, then the second is synthesized by the body itself under the influence of sunlight. It is vitamin D 3 that in most cases provides the body’s needs, however, in some cases it is simply impossible to do without additional supply of form D 2.

Vitamin D is absorbed in the body only in combination with vegetable oils, since it belongs to the fat-soluble group of substances. Like all components that react with organic solvents, it is deposited in the liver and can be removed from there in cases of temporary deficiency. This property is of particular importance in winter, when the amount of sunlight and natural sources of calciferol decreases; Having received a sufficient amount of vitamin D over the summer, you don’t have to worry about its deficiency in the winter.

What is vitamin D for?

The functions of calciferol in the body are simply enormous. This versatility is explained by the fact that the substance acts not only as a vitamin, but also as a hormone. Entering the digestive tract, it is absorbed in the small intestine, responding to the effects of bile. Most of the vitamin D is absorbed in the middle part of the small intestine, while the rest remains in the ileum.

The main function of calciferol can be read from the context, because vitamin D has a rather “telling” name: normal mineral metabolism in general and the absorption of calcium in particular are impossible without a sufficient amount of this substance. Calciferol regulates the deposition of calcium in bone tissue, thereby preventing its softening and subsequent serious injuries to the musculoskeletal system. When metabolizing molecules of Ca, Mg and phosphates, it accelerates all metabolic processes, and also has a positive effect on the permeability of intestinal epithelial cells for Ca and P. And if a lack of phosphorus is rare, then a lack of calcium in the body is a fairly common and, unfortunately, significant phenomenon .

As a hormone, vitamin D in the body also affects calcium metabolism: entering the cells of the small intestine, it inhibits the synthesis of a carrier protein, which subsequently binds to calcium and transports it, and in kidney and muscle cells acts as a catalyst in the processes of reabsorption of Ca molecules .

However, calcium metabolism is far from the only function of this substance: vitamin D has quite a wide range of uses. Thus, calciferol directly affects the body’s immune responses, reducing the risk of dermatological problems. A normal amount of vitamin is the best prevention of pathologies of the cardiovascular system, including atherosclerosis, heart rhythm disturbances, regular increases in blood pressure and associated hypertensive crises.

Vitamin D: use daily

The daily requirement of calciferol depends not only on age and gender, but also on the characteristics of the geographical location, belonging to a particular race and the condition of the body. For example, in people lacking sunlight, the need to obtain vitamin D from outside increases significantly. This category of persons includes:

people who are nocturnal (working night shifts or preferring night walks to day walks);
living in countries geographically located at high latitudes;
bedridden patients who are physically unable to regularly spend time in the fresh air;
residents of cities (usually megacities), characterized by a particularly polluted atmosphere that does not transmit the full spectrum of ultraviolet rays: even if there is enough sun in such an area, the necessary waves will be filtered out by chemical compounds that pollute the air.

Skin color also affects the natural synthesis of vitamin D: the darker it is, the less substance is formed under the influence of ultraviolet radiation. The need for calciferol changes similarly with age, because in older people the body’s ability to convert provitamins into calciferol is significantly lower.

The following daily norms for vitamin D use have been established in the Russian Federation:

This does not mean that this amount of calciferol should be obtained from food every day: if you lead an active lifestyle, regularly walk in the fresh air, and get enough sunlight, vitamin D intake from food is not required in principle. It is believed that just 20 minutes in direct sunlight is enough for vitamin D to be produced in the amount required for an adult. Walking in the morning and evening hours, when the sun is not so hot, is especially useful.

Lack of vitamin D in the body

Hypovitaminosis D scares young mothers almost to the point of trembling: after all, a growing body vitally needs calcium, and therefore vitamin D. With its deficiency, the baby can develop rickets, which is accompanied not only by serious changes in the skeleton, but also by damage to internal organs. The heart and lungs suffer especially, because they are located in the chest, which begins to deform first. But even knowing why a newborn needs vitamin D, you shouldn’t stuff it with synthetic supplements almost from the first days; It is enough to ensure that he is in the fresh air every day and receives a sufficient portion of sunlight. If the baby is breastfed, the mother also needs regular walks during daylight hours: after all, the baby will also receive useful substances with breast milk.

Low levels of vitamin D in the blood are dangerous not only in infancy, but also in older age. Thus, with a lack of calciferol, adults can develop a dangerous bone disease - osteoporosis. It is characterized by softening of bones, their pathological fragility and deformation. This means that even the slightest injury, which would cause at most a bruise in a healthy person, can lead to complex fractures, which will also heal extremely slowly. Injuries to the femoral neck, spine and splinter fractures are considered especially serious: it is very difficult to recover from them.

In addition, hypovitaminosis D is associated with the development of diabetes, especially in adolescence, as well as with disturbances in the functionality of the thyroid gland, adequate blood clotting and the development of psoriasis. Among other things, studies are currently underway confirming that calciferol reduces the risk of developing cancer.

Is excess vitamin D dangerous?

Despite its undoubted benefits, in large quantities calciferol can cause serious damage to the body. When calcium levels in the blood increase, the kidneys, heart, and circulatory system can be damaged. In the initial stages, hypervitaminosis D will manifest itself with the following symptoms:

classic picture of intoxication: apathy, lethargy, lack of appetite, dizziness;
pain in the joints, as well as muscle spasms;
persistent headache.

If measures are not taken, the clinical picture will be complemented by fever, pressure surges, bradycardia and convulsions.

However, pathologically high levels of vitamin D in the blood are quite rare. Most often it occurs with prolonged or excessive use of synthetic additives. It is impossible to encounter hypervitaminosis by sunbathing and regularly consuming foods enriched with calciferol.

Vitamin D: what foods contain it?

As a rule, ergocalciferol enters the body from food. Its share in providing the body with vitamin D is negligible and amounts to about 10% of the total human need, however, it is still not worth completely excluding fortified foods from the diet: they can become a tangible support for the body, especially in the autumn-winter period, when the number of cloudy days increases. What products should you pay attention to first?

Foods containing the most vitamin D

Forest mushrooms. Chanterelles deservedly took first place on this list. These unpretentious mushrooms grow almost everywhere, however, it is still not worth collecting them within the city limits and along highways: they accumulate many harmful substances, including toxic compounds from exhaust gases, heavy metals, etc. But chanterelles grown in forest array will be extremely useful. It is noteworthy that the amount of vitamin D in them does not decrease after salting or drying. This means that you can prepare dried chanterelles for the winter and pamper your loved ones with aromatic and healthy mushroom dishes all year round. Of course, yogis believe that this type of product negatively affects the state of energy, but if you are, for example, at the stage of initial vegetarianism and are experimenting with recipes, then a little mushrooms are unlikely to harm you much.

Herbs. Large amounts of ergocalciferol can be found in parsley, dandelion, nettle, horsetail and alfalfa. Some of these herbs can be used as the main ingredient for preparing fortified dishes, while others are good only as seasonings. For example, in the summer, doctors recommend regularly preparing nettle soup: this unique plant contains many useful components, including vitamin D. Delicious jam is often prepared from dandelions, which is also perfectly stored in the refrigerator. But parsley can only be used as a herb, but you can put it in almost any dish, be it soup, salad or side dish.