Vitamins: a complete collection of misconceptions

Spring is the right time to remember about vitamins. But not so much about what everyone already knows, but about a lot of myths that many people take for medical facts.

Vitamin educational programVitamins (Latin vita – life) are low–molecular organic compounds that are not synthesized in the human body (or are synthesized in insufficient quantities) and are an active part of many enzymes or starting substances for the synthesis of hormones.

A person's daily need for various vitamins ranges from a few micrograms to tens of milligrams. There are no more common signs of vitamins, and the only generally accepted classification of vitamins is the division into water– and fat-soluble.

By structure, vitamins belong to a variety of classes of chemical compounds, and their functions in the body are very diverse – not only in different vitamins, but also in each individual. For example, vitamin E is traditionally considered primarily necessary for the normal functioning of the genital glands, but this role at the level of the whole organism is only the first in terms of discovery. It protects unsaturated fatty acids of cell membranes from oxidation, promotes the absorption of fats and, accordingly, other fat-soluble vitamins, acts as an antioxidant, neutralizing free radicals, and thereby prevents the formation of cancer cells and slows down the aging process, etc. (to understand how it does this, you need to first learn a three-kilogram textbook of biochemistry). For most other vitamins, the main one is also considered to be the most visible symptom to the naked eye, according to which it was once discovered. So the belief that vitamin D helps from rickets, C – from scurvy, B12 is necessary for hematopoiesis, etc. is a common, although not the main, misconception about vitamins.

Water–soluble vitamins are vitamin C (ascorbic acid), P (bioflavonoids), PP (nicotinic acid) and B vitamins: thiamine (B1), riboflavin (B2), pantothenic acid (B3), pyridoxine (B6), folacin, or folic acid (B9), cobalamin (B12). The group of fat–soluble vitamins includes vitamins A (retinol) and carotenoids, D (calciferol), E (tocopherol) and K. In addition to 13 vitamins, about the same number of vitamin-like substances are known - B13 (orotic acid), B15 (pangamic acid), H (biotin), F (omega-3-unsaturated fatty acids acids), paraaminobenzolic acid, inositol, choline, acetylcholine, etc.

In addition to vitamins themselves, multivitamin preparations usually contain compounds of minerals – micro- and macroelements.

Macronutrients are found in food in large quantities. Their daily norm for adults is measured in grams: phosphorus – 2 g, calcium – 1 g, magnesium – 0.5-0.6 g. Both they and sulfur, silicon, sodium, potassium, chlorine enter the body in sufficient quantities with food, and their additional intake in the form of tablets or products rich in certain macronutrients is needed in special cases: cheese is a good source not only of calcium, but also of sulfur, which contributes, among other things, to the excretion of heavy metals from the body; dried fruits contain a lot of potassium, an excess of which is necessary for heart diseases and taking certain medications, etc.

Trace elements are needed in small and microscopic quantities, from milligrams to tens of micrograms. Trace elements are often not enough in the traditional diet: the average resident of Russia with water and food receives 40 micrograms of iodine per day at a rate of 200. Mineral elements and vitamins are usually related to each other: antioxidants and oncoprotectors (or, at least, anti–carcinogens) – selenium and vitamin E - work together many times better than separately; calcium is not absorbed without vitamin D; vitamin B12 is needed for iron absorption, which includes another trace element, cobalt. The main of about 30 known trace elements are bromine, vanadium, iron, iodine, cobalt, silicon, manganese, copper, molybdenum, selenium, fluorine, chromium and zinc.

Violations of the activity of various body systems can cause a lack of any mineral substance, but the old truth is also true for them: "every poison is medicine, and every medicine is poison." Salt was once a valuable food additive, but it has long been blacklisted: in modern conditions, it is recommended to limit the intake of sodium and chlorine into the body. If, in pursuit of calcium, you eat almost one milk (for several years, 5 liters a day – the law is not written for enthusiasts), you can irreversibly destroy the kidneys. Zinc is necessary for the synthesis of many enzymes, including those that ensure the normal functioning of the "second heart of a man" – the prostate gland, but welders have acute zinc poisoning (and chronic – another trace element, manganese). At the end of the 1980s, in the Chernobyl trace zone, many, hearing the ringing about the dangers of radioactive iodine, poisoned themselves with iodine tincture, taking thousands of daily norms in a few drops.

But back to the vitamins. We will not tell the story of their discovery and retell how each of them acts on a variety of biochemical processes occurring in the body. Let's dedicate this article to the mistakes in vitamin therapy – what many vitamin consumers and even doctors consider to be the truth and what in fact is absolutely not true.

Let's start with the most important and harmful misconception:

The need for vitamins can be fully met through proper nutrition

It is impossible – for a number of reasons. First, man too quickly "descended from a monkey." Modern chimpanzees, gorillas and our other relatives fill their bellies with a huge amount of plant food all day, while plucked directly from a tree in a tropical forest. And the vitamin content in wild–growing tops and roots is ten times greater than in cultivated ones: the selection of agricultural varieties for thousands of years was not based on their usefulness, but on more obvious signs - yield, satiety and resistance to diseases. Hypovitaminosis was hardly the No. 1 problem in the nutrition of ancient hunters and gatherers, but with the transition to agriculture, our ancestors, having provided themselves with a more reliable and abundant source of calories, began to experience a shortage of vitamins, trace elements and other micronutrients (micro – understandable, nutricium – nutrition). Back in the XIX century in Japan, up to 50,000 poor people, who ate mainly refined rice, died from beriberi -beriberi – vitamin B1 every year. Vitamin PP (nicotinic acid) in corn is contained in a bound form, and its predecessor, the essential amino acid tryptophan, is in negligible amounts, and those who fed on tortillas or hominy alone were sick and died from pellagra. In poor Asian countries, at least a million people still die a year and half a million go blind due to the fact that there are no carotenoids in rice - precursors of vitamin A (actually vitamin A is most in the liver, caviar and other meat and fish products, and the first symptom of its hypovitaminosis is a violation of twilight vision, "chicken blindness").

Moderate and even pronounced hypovitaminosis in Russia is present in at least three quarters of the population. A close problem is dysmicroelementosis, an excess of some and a lack of other trace elements. For example, moderate iodine deficiency is a widespread phenomenon, even in coastal areas. Cretinism (alas, only as a disease caused by the complete absence of iodine in water and food) is no longer found, but, according to some reports, the lack of iodine reduces the intelligence coefficient by about 15%. And it certainly leads to an increase in the likelihood of thyroid diseases.

A soldier of the pre-revolutionary Russian army with a daily energy consumption of 5000-6000 kcal was given a daily allowance, including, among other things, 3 pounds of black bread and a pound of meat. One and a half to two thousand kilocalories, which are enough for a day of sedentary work and recumbent rest, guarantee you a shortage of about 50% of the norm of about half of the known vitamins. Especially in the case when calories are obtained from refined, frozen, sterilized products, etc. And even with the most balanced, high-calorie and "natural" diet, the lack of some vitamins in the diet can reach up to 30% of the norm. So take multivitamins – 365 tablets a year.

Synthetic vitamins are worse than natural ones

Many vitamins are extracted from natural raw materials, like PP from citrus peel or, like B12, from the culture of the same bacteria that synthesize it in the intestine. In natural sources, vitamins are hidden behind cell walls and are associated with proteins, of which they are coenzymes, and how much you assimilate them, and how much will disappear, depends on many factors: for example, fat-soluble carotenoids are much more fully absorbed from carrots, finely grated and stewed with sour cream containing emulsified fat, and vitamin C, on the contrary, it decomposes quickly when heated. By the way, did you know that when natural rosehip syrup is evaporated, vitamin C is completely destroyed, and only at the last stage of cooking synthetic ascorbic acid is added to it? In the pharmacy, nothing happens with vitamins until the end of the shelf life (and in fact – for several more years), and in vegetables and fruits their content decreases with each month of storage, and even more so during cooking. And after cooking, even in the refrigerator – even faster: in a sliced salad after a few hours, vitamins become several times less. Most vitamins in natural sources are present in the form of a number of substances similar in structure, but different in effectiveness. Pharmacy preparations contain those variants of vitamin molecules and organic compounds of trace elements that are easier to digest and act most effectively. Vitamins obtained by chemical synthesis (like vitamin C, which is made both biotechnologically and purely chemically) are no different from natural ones: in structure they are simple molecules in which there simply cannot be any "life force".

You can stock up on vitamins for the future

Fat–soluble (A, E and especially D, which is synthesized in the skin under the action of ultraviolet light) - for a while it is possible. Water-soluble very quickly find a hole for themselves: for example, the concentration of vitamin C in the blood returns to its initial state 4-6 hours after taking a shock dose.

Vitamins are needed only in the North

In extreme conditions, they are really needed – including in high latitudes, with their polar night and monotonous and more "canned" than in the south, nutrition. But residents of even the most fertile lands also need additional intake of vitamins – except that they do not need an extra microgram of vitamin D in winter.

Vitamins are needed only in winter

In winter and spring they are more necessary. If you eat a lot of fresh herbs, vegetables and fruits in the summer, you can give up pills for a while. If you do not refuse, then there will be no harm.

Vitamins are needed only by patients

In a number of diseases, increased doses of certain vitamins are indicated: for example, vitamin K, which increases blood clotting, is the first thing prescribed for internal and uterine bleeding, E – for some reproductive disorders, PP and C – for increased capillary permeability, the whole group B – for some diseases of the peripheral nervous system. And multivitamin pills are not medicines. They do not have any specific effect and are needed not for treatment, but for the prevention of diseases. But for those who do not think about vitamins at all or believe that they will get by with what they get with food, any acute or chronic illness is an occasion to think about the benefits of fortification of the body.

The more, the better

Everything is good in moderation. Prolonged excess of the dose of vitamins and other micronutrients can do more harm than good, as beta-carotene, which in moderate doses is, in particular, a recognized oncoprotector, and with a long-term and pronounced overdose increases the likelihood of lung cancer in smokers (this phenomenon was called the beta–carotene paradox). Even with obvious vitamin deficiency, doctors prescribe a maximum of a triple dose of vitamins – the body simply will not absorb more.

Horse doses of vitamin... help from ...

Articles on this topic regularly appear in the medical literature, but after 10-20 years, when there are enough scattered studies on different population groups, with different dosages, etc., to conduct a meta-analysis of them, it turns out that this is another myth. Usually, the results of such an analysis are as follows: yes, the lack of this vitamin (or other micronutrient) is associated with a greater frequency and/or severity of this disease (most often with one or more forms of cancer), a dose 2-5 times higher than the physiological norm does not affect either the incidence or the the course of the disease, and the optimal dosage is approximately the one indicated in all reference books.

A gram of ascorbic acid a day protects against colds and generally from everything in the world

Twice Nobel laureates are also wrong: hyper- and megadoses of vitamin C (up to 1 and even 5 g per day at a rate of 50 mg), which came into fashion with the filing of Linus Pauling, as it turned out many years ago, do not benefit ordinary citizens. Reduction of morbidity (by several percent) and duration of acute respiratory infections (less than one day) compared with the control group, which took the usual amount of ascorbic acid, it was possible to identify only in a few studies – in skiers and commandos who trained in the winter in the North. But there will be no great harm from megadoses of vitamin C, except for hypovitaminosis B12 or kidney stones.

Better a shortage than a bust

To sort out vitamins, you need to try very hard. Of course, there are exceptions, especially for the minerals and trace elements included in the majority of multivitamin complexes: those who eat a portion of cottage cheese every day do not need additional calcium intake, and those who work in the electroplating shop – chromium, zinc and nickel. In some areas, in the water, soil and ultimately in the organisms of people living there, there are excessive amounts of fluorine, iron, selenium and other trace elements, or even lead, aluminum and other substances, the benefits of which are unknown, and the harm is beyond doubt. The composition of multivitamin tablets is selected so that in the vast majority of cases they cover the deficiency of micronutrients in the average consumer and guarantee the impossibility of a serious overdose, even with daily and prolonged intake in addition to the usual diet of several tablets, not one.

Hypervitaminosis in most cases occurs with prolonged consumption of vitamins (and only fat-soluble ones that accumulate in the body) in doses orders of magnitude higher than normal. Most often, and then extremely rarely, this occurs in the practice of pediatricians: if from a big mind, instead of one drop a week, give a newborn a teaspoon of vitamin D a day… The rest is on the verge of jokes. I read somewhere either the truth or a plausible fiction, how almost all the housewives in the village bought a vitamin D solution stolen from a poultry farm under the guise of sunflower oil. Or – they say it happened – after reading nonsense about the benefits of carotenoids "at cancer", people started drinking carrot juice liters a day, and some of this did not just turn yellow, but drank themselves to death. It is impossible to assimilate more than the maximum of vitamins determined by nature through the gastrointestinal tract with a single intake: at each stage of absorption into the intestinal epithelium, transfer to the blood, and from it to tissues and cells, transport proteins and receptors on the cell surface are needed, the number of which is limited. But just in case, many companies pack vitamins in jars with "child–resistant" lids - so that the baby does not devour his mother's three-month norm at a time.

There are allergies from vitamins

An allergy may develop to some drug that you have taken before and part of the molecule of which is similar in structure to one of the vitamins. But even in this case, an allergic reaction will manifest itself with intramuscular or intravenous administration of this vitamin, and not after taking one tablet after a meal. Sometimes allergies can be caused by dyes, fillers and flavoring substances included in the tablets. In this case, you can switch to vitamins from another company – perhaps they do not have this particular component.

With constant intake of vitamins, addiction develops to them

Getting used to oxygen, water, as well as fats, proteins and carbohydrates does not frighten anyone. And the so-called withdrawal syndrome is not typical for vitamins: after stopping taking them, the body simply returns to a state of hypovitaminosis.

People who do not take vitamins feel great

Yes – about the same way a tree growing on a rock or in a swamp feels great. Symptoms of moderate polyhypovitaminosis like general weakness and lethargy are difficult to notice. It is also difficult to guess that dry skin and brittle hair should be covered up not with creams and shampoos externally, but by ingestion of vitamin A and stewed carrots, that sleep disorders, irritability and fatigue or seborrheic dermatitis and acne are signs not of neurosis or hormonal imbalance, but of a shortage of any of the B vitamins, and so on further along the entire list of vitamins and trace elements, from A to Zink. Pronounced hypo- and vitamin deficiencies are most often secondary, caused by some disease in which their assimilation is disrupted. (And vice versa: gastritis and anemia – a violation of hematopoietic function, visible to the naked eye by the cyanosis of the lips – can be both a consequence and cause of hypovitaminosis B12 and / or iron deficiency.) And the relationship of hypovitaminosis and increased morbidity, reduced resistance of the body, etc., up to a higher frequency of fractures with a lack of vitamin D and calcium or increased incidence of prostate cancer with a lack of vitamin E and selenium, are noticeable only when statistically analyzing large samples – thousands or even hundreds of thousands of people, and often – when observed for several (sometimes – more than ten) years.

Vitamins and mineral elements prevent the assimilation of each other

This point of view is especially actively defended by manufacturers and sellers of vitamin and mineral complexes for separate intake. And in confirmation, they cite experimental data in which one of the antagonists entered the body in the usual amount, and the other in tens of times larger doses (above we mentioned hypovitaminosis B12 as a result of fascination with ascorbic acid). Experts' opinions on the expediency of dividing the usual daily dose of vitamins and minerals into 2-3 tablets differ exactly the opposite.

...Nourishes my hair from the roots to the tips

Vitamins are like a dog's fifth leg to hair: the cells in them are inanimate, and no biochemical processes occur in them. Vitamins from shampoo will not reach the hair follicles: the skin passes water solutions very reluctantly, and in order for small molecules to penetrate through it, it is necessary to apply either a long-term application (for example, a nicotine patch), or intensive rubbing. For example, in a recently published article, the authors claim that a cream containing 7% caffeine helped the experimental ladies a lot to lose fat deposits from problem areas. For a couple of minutes, which you just sit with a soapy head, nothing will have time to soak into the skin, after rinsing, homeopathic amounts of vitamin will remain on the skin… Most likely, the fortification of shampoos is just a publicity stunt.

An apple a day keeps the doctor away

The Russian equivalent of this proverb – "the bow of seven diseases" – is also incorrect. Vegetables and fruits (raw!) They can serve as a more or less reliable source of vitamin C, folic acid (vitamin B9) and carotene. To get a daily allowance of vitamin C, you need to drink 3-4 liters of apple juice – from very fresh apples or canned, which contains about as many vitamins as indicated on the package. Leafy vegetables lose about half of vitamin C a day after harvesting, peeled vegetables and fruits – after several months of storage. The same thing happens with other vitamins and their sources. Most vitamins decompose when heated and under the influence of ultraviolet radiation – do not keep a bottle of vegetable oil on the windowsill so that the vitamin E added to it does not collapse. And when boiling, and even more so when frying, many vitamins decompose by the minute. And if you read the phrase "100 g of buckwheat contains ..." or "100 g of veal contains ...", you were deceived at least twice. Firstly, this amount of vitamin is contained in the raw product, and not in the finished dish. Secondly, kilometer-long tables of vitamin content in products have been roaming from one directory to another for at least half a century, and during this time vitamins and other micronutrients in new, more productive and high-calorie varieties of plants and in the pork, beef and chicken fed by them have become much (on average twice) less. True, many products have been fortified recently, but in general it is impossible to get enough vitamins from food. On the other hand, the benefits of proper nutrition do not become less from this.

These vitamins are better than those

Usually multivitamin preparations contain at least 11 out of 13 vitamins known to science and about the same amount of mineral elements, each – from 50 to 150% of the daily norm: components, the shortage of which is extremely rare – less, and substances especially useful for all or individual groups of the population – just in case more. The norms in different countries vary, including depending on the composition of traditional nutrition, but not much, so you can ignore who set this norm: the American FDA, the WHO European Bureau or the USSR People's Commissariat of Health. In the preparations of the same company, specially designed for pregnant and lactating women, the elderly, athletes, smokers, etc., the amount of individual substances may vary several times. Of course, optimal dosages are also selected for children, from infants to teenagers. Otherwise, as they once said in a commercial, everyone is the same! But if the packaging of a "unique natural food additive made from environmentally friendly raw materials" does not indicate a percentage of the recommended norm or does not say at all how many milli- and micrograms or international units (IU) one serving contains, this is a reason to think.

The newest legend: vitamins are harmful!

A year ago, the news spread around the world: Swedish scientists proved that vitamin supplements kill people! Taking antioxidants on average increases the mortality rate by 5%!! Separately, vitamin E – by 4%, beta-carotene – by 7%, vitamin A – by 16%!!! Or even more – for sure, many data on the harm of vitamins remain unpublished!

It is very easy to confuse cause and effect with a formal approach to mathematical data analysis, and the results of this study caused a wave of criticism. From the regression equations and correlations obtained by the authors of the sensational study (Bjelakovic et al., JAMA, 2007), we can draw the opposite and more plausible conclusion: those elderly people take more general restoratives (the authors analyzed only the results of observations of older age groups) who feel worse and are more ill – and, accordingly, rather die. But another legend will surely be walking around the media and public consciousness for as long as other myths about vitamins.

Alexander Chubenko
Portal "Eternal youth" www.vechnayamolodost.ruThe journal version of the article was published in Popular Mechanics No. 3-2008

01.04.2008