Question to expert: Is it true we all need to drink vitamin D
Interview: Valery Yudin
Answers to most questions that concern us we are all used to searching online. In this series of materials we ask precisely such questions - burning, unexpected or widespread - to professionals in various fields.
The global interest in a healthy lifestyle draws many not only to proper nutrition and regimen, but also to the question whether various dietary supplements and pharmacological drugs can provide real support to the body. In many cases, you can only shrug, but doctors still recommend paying attention, for example, to vitamin D, which has recently been spoken about more and more. Dermatocosmetologist Yulia Shcherbatova explains why this vitamin is so important and where it comes from to a resident of a megalopolis.
Julia Shcherbatova
dermatocosmetologist, candidate of medical sciences, founder of "Clinic of modern cosmetology Yulia Shcherbatova"
Vitamin D is not one, but a whole group of substances with prohormone activity. That is, they are not hormones themselves, but turn into them as a result of biochemical reactions in our body. There are two important forms of vitamin D for humans: D2 (ergocalciferol) and D3 (cholecalciferol). The first enters our body only with food, and the second we not only get from food, but we can synthesize ourselves under the influence of the sun. Passing through the liver, both forms turn into 25-hydroxyvitamin D (abbreviated as 25 (HO) D). The content of this particular form can be quite accurately measured in the blood plasma, therefore, it is she who most often appears in the analyzes. Then 25 (HO) D passes through the kidneys and turns into 1,25-dihydroxycholecalciferol (calcitriol). Actually, this is the active form of vitamin D in the body. Such are the adventures.
Vitamin D helps us absorb calcium and phosphorus, due to which bone tissue is formed (which, for example, prevents the risk of fractures in the elderly). In addition, he controls a huge number of genes, and some of them are associated with the risk of developing cancer or autoimmune diseases and infections. There are many studies on the role of vitamin D in the prevention of breast cancer, heart disease, multiple sclerosis, osteoporosis and even schizophrenia.
In addition, vitamin D plays a huge role in fat metabolism: overweight people almost always have a shortage of it. As for oncology, then, somewhat rough, we can say that vitamin D is an oncoprotector. When the level of hormones falls, which occurs in the region of forty-five years, the probability of proliferation of tissues of organs increases - uncontrolled multiplication of the cell mass. As we understand, cells can be either benign or not. If not, malignant tumors develop, the frequency of which becomes higher with age. A sufficient level of vitamin D reduces these risks and balances the situation. It is customary to say about many diseases that "this is heredity." And it is. But we should not forget about the phenomenon of gene expression. Heredity can manifest or not. And cholecalciferol controls about 3% of the genome, which is quite a lot. So keep in mind that vitamin D in sufficient quantity can make it so that in your case the heredity does not work.
What happens when it is deficient? A study published in the journal Archives of Internal Medicine showed that low levels of vitamin D in blood plasma were associated with a doubled risk of death for patients in general and of cardiovascular diseases in particular. A large study of aging in the Netherlands found a link between vitamin D deficiency and depression in patients aged 65 to 95 years. In addition to depression and cardiovascular diseases, vitamin D deficiency can lead to obesity, weakened immunity, and brittle bones. Extreme manifestations of beriberi are rickets in children and osteomalacia in adults. But most often the deficit is manifested by a decline in strength and depression. According to the most conservative estimates, every 7th person in the world is susceptible to vitamin D deficiency, while residents of northern latitudes (and Russia in particular) almost 100% of the population have it to one degree or another, especially in autumn and winter. So if the forces have left you and you are depressed, pass the tests.
According to the most conservative estimates, every 7th person in the world is susceptible to vitamin D deficiency, and almost 100% of the population in varying degrees have it in northern latitudes
We have already found out that a person receives vitamin D either from food (for example, when he eats fatty fish, forest mushrooms, pork, eggs, cheese, butter, caviar, some algae), or under the influence of sunlight. True, there are several "but". The diet of an ordinary person, in principle, can not give the body the right amount of vitamin D. And if you set yourself the goal of still getting a daily dose of vitamin from food, you have to eat fish every day in kilograms. Unfortunately, it will not end well.
I already wrote about problems with fish in my blog: briefly, the world's water bodies are so heavily contaminated with dioxin and heavy metals, and the fish we eat lives in this water for so long that it accumulates several times more toxins in itself, than water itself contains. Details on this can be found on the PETA website, but according to a report to the US Environmental Protection Agency prepared for the congress, fish is generally the main source of mercury in humans and animals. By the way, if you are interested in seeing how much mercury is contained in various seafood, you can do it here. Does this mean that seafood is better not to eat? Not at all. But it is better to keep track of what exactly is on your plate, and not to arrange a fish mono-diet for yourself.
So, only one diet, without the sun, the body's need for vitamin D can not be met. And then a second problem arises: how to spend enough time in the sun and at the same time protect yourself from risks? The list of these risks is a topic for a separate discussion. Ultraviolet not only accelerates skin aging like nothing else, but is also directly related to the danger of development, for example, melanoma. By the way, UV rays not only accelerate aging, slowing down collagen synthesis and destroying existing collagen fibers, but also enhance the formation of free radicals in the skin. And free radical oxidation is another one of the key causes of skin aging. In short, worse than being in the sun for the skin can only be in the sun with a cigarette. So can you stay in the sun without harming your skin? Unfortunately no. Ultraviolet light does not penetrate through clothing, glass or cream with SPF, and vitamin D synthesis does not occur. And in any case, above the 37th parallel, the sun shines so weakly that it does not allow you to get the right amount of vitamin D even in summer. Moscow, if anything, is above the 50th parallel.
Thus, neither a special diet nor sun exposure with all the attendant risks can provide the inhabitants of northern latitudes with the right level of vitamin D. Fortunately, there are additional sources in the form of dietary supplements. True, it is not worthwhile to prescribe them yourself: even though almost everyone needs a vitamin, the dosage and regimen can vary greatly. I specifically do not indicate the rate of vitamin D intake: not only because in Russia and in the world they are different, but also because I consider self-diagnostics and answers "I have been tested, I have everything in order" as a separate evil. Analyzes should be prescribed and read by a doctor, and it is he who informs the patient how his results are interpreted. In short, you can only assign vitamin D to you, a nutritionist or endocrinologist, and only after tests. Probably, over time, the dosage will need to be adjusted, so get ready for control checks every two to three months. Since vitamins are involved in the metabolism, it is better to drink them during the main meal or immediately after. The main reception is when you eat the most (for someone it's breakfast, for someone lunch).
How to choose the right vitamin D? First, it should be fat soluble and better in capsules (so taking it is much easier and more pleasant than in liquid form). Secondly, make sure that it is made from small varieties of fish: they have time to accumulate the least amount of toxins. Third, get ready to order the drug on the Internet or carry it from abroad. Unfortunately, in Russia it is produced and sold exclusively in low prophylactic dosages (for example, 400 or 600 IU), and sometimes it is even a complex of vitamins (for example, basic fat-soluble vitamins A, D, E). These should not be taken at all if you only need vitamin D. In high therapeutic dosages (5,000 IU and above) and American brands are producing vitamin D in a good degree of purification. But, be that as it may, it is better to entrust the choice of the drug to the doctor. The main thing - find a competent specialist.
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