Advertising on the portal

What does vitamin D contribute to? Why is vitamin D needed in the body and where is it found?

The main argument of doctors in favor of moderate tanning is that in the sun more than 90% of vitamin D is formed in the body, while less than 10% comes from food. As a result, most residents of the Northern Hemisphere are deficient in this beneficial compound.

However, in lately an alternative has appeared - store shelves are filled with milk, yoghurts, cookies, bread, breakfast cereals, the labels of which say: “additionally enriched with vitamin D.” Is it worth paying extra for such products? Are “sun” and food vitamins equivalent in benefits?

By the way
A lack of vitamin D in the body can lead to the development of rickets in children and osteoporosis in adults. And recently, the role of vitamin D in providing normal operation immune system, regulation blood pressure, prevention diabetes mellitus and even some cancers.

In products it is most abundant in oily fish(salmon, sardines, mackerel), eggs, especially when the feed is enriched with vitamin D.

An adult's requirement for vitamin D is 5 mcg per day (200 IU). A blood test will help determine whether your body is provided with it. The norm is the presence in plasma of at least 50 nmol/l of a compound called 25-hydroxyvitamin D.

There are reasons for doubt: under the influence of ultraviolet radiation, vitamin D3 is produced in the skin, it also comes from animal food, but in plant products There is another connection - D2.

Studies have proven that both vitamins enter the liver, where they are converted into calcitriol, that is, both are equally beneficial for health, says Valery Kuznetsov, Doctor of Medical Sciences, Professor of the Department of Human Ecology and Hygiene environment First Moscow State Medical University them. I. M. Sechenova. - However, there is one caveat: if foods with low or no calcium content are fortified with vitamin D, then the risk of developing osteoporosis increases, especially in people who consume little dairy products. The fact is that vitamin D helps the body absorb calcium. But, if there is nothing to absorb from food, it takes calcium from the bones (not from the intestines!), thereby reducing their density.

So milk fortified with vitamin D is still healthier than bread.

However, if not medical contraindications In summer, it is easier and more natural to get your vitamin D requirement by sunbathing. To do this, 10–15 minutes of exposure to direct sunlight is enough (with with open hands and face) three times a week. But keep in mind: sunscreens with a protection factor (SPF) of more than 15 completely block the production of vitamin D in the body. The third option - additional vitamin D intake in the form of medications is usually required for infants under one year of age (daily), children preschool age(courses), elderly people, with inflammatory bowel diseases (colitis, Crohn's disease, etc.), obesity.

For whom is solarium prohibited?

As summer approaches, tanning salons become more active. Their motto: it is better to prepare your skin for summer in a solarium, so as not to get sunburned on the beach.

It’s difficult to do anything stupid, experts say. The World Health Organization (WHO) has published a document that says: tanning beds are harmful and dangerous to use.

First of all, WHO draws attention to the problem of skin cancer, which makes up a third of all cancers, says Oleg Grigoriev, head of the laboratory of radiobiology and hygiene of non-ionizing radiation, FMBC named after. A. I. Burnazyan FMBA of Russia. - Among the causes that cause skin cancer, the first place is the use of solariums. In its recommendations regarding this type of cosmetic procedure, WHO draws special attention to ban solariums for children under 18 years of age. Doctors are based on research from the International Agency for Research on Cancer, which has been collecting statistics since 1995 and found that there is a direct relationship between visiting a solarium and the occurrence of skin cancer. Already at the end of 2010, Russian sanitary standards for the cosmetology industry, which reflect these WHO standards. That is, young people under 18 years of age in our country are not officially allowed to use solariums. But who will control this? According to the norms, salon owners must not allow children in the solarium. The administrator is also obliged to warn each client about the danger of overexposure, etc. In fact, rarely will anyone ask what your illness is, and they are unlikely to prohibit you from sunbathing for “extra” minutes.

Initially, tanning beds were developed only for medical purposes and were always used under the supervision of medical professionals to stimulate the production of vitamin D. After all, in a solarium you are not just exposed to ultraviolet rays. During the irradiation process, the skin becomes dehydrated, metabolic processes in the cell are disrupted, the blood flow changes, and with it the reaction to medications, cosmetics, etc. A change in the surface blood flow entails a change in the internal blood flow.

Vitamin D is a nutrient that helps prevent many chronic diseases, including various types of cancer. However, many people are deficient in vitamin D because most foods are low in vitamin D. In fact, the richest source of this vitamin is sunlight, however, prolonged exposure to the sun is harmful to the skin. Maintaining adequate vitamin D levels can be challenging. Nevertheless, proper diet nutrition, reasonable use of sunlight and taking those recommended by your doctor food additives will help you provide for your body sufficient quantity this important vitamin.

Steps

Increase your vitamin D intake

    Talk to your doctor about taking vitamin D supplements. Although vitamin D is important for health, not all foods are a good source of it. Because of this, it is impossible to provide your body with enough vitamin D through diet alone. You should not only include in your diet foods rich in this quite rare vitamin, but also take nutritional supplements with it. Vitamin D supplements can be purchased in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).

    If you are vegan, take vitamin D2. Vitamin D3 is a more complex compound and is obtained from animal products. Despite the health benefits, this vitamin may not be suitable for many vegans and vegetarians. On the other hand, vitamin D2 supplements are synthesized from mold and do not contain any animal products.

    Increase your time in the sun carefully. Although vitamin D is not often found in food products, it is formed in the body under the influence of sunlight. However, you should strike a balance and not be in the sun too little or too long - in the first case you will not get enough vitamin D, and in the second you risk earning sunburn. It is enough to spend 10-20 minutes in the sun twice a week, and at the same time apply sunscreen only to the face. You can also sunbathe for 2-3 minutes several times a week and also apply sunscreen only to your face. In any case, you should not swim within an hour after you have been in the sun.

    Consider factors that may affect vitamin D production from exposure to sunlight. One of them is latitude - the closer to the equator you live, the more solar radiation you will receive. In addition, the production of vitamin D is influenced by the natural color of the skin: due to lower melanin content, pale skin produces more of this vitamin than darker skin.

    • Although some factors are difficult to change, you can choose what time of day to go out into the sun. Choose a time around mid-day rather than in the morning or evening. In the middle of the day solar radiation most intensely, which promotes the release of more vitamin D.
    • Expose yourself to the sun as much as possible O larger areas of skin. During those few minutes when you deliberately lie in the sun, do not wear closed clothing with long legs and sleeves! The larger the area of ​​skin exposed to sunlight, the more vitamin D your body will produce. However, keep it in moderation. If you live in an area with very bright sunlight, be careful not to get sunburned.
    • Remember that sunlight is quite intense even in cloudy weather.
    • The human body stores vitamin D, so sufficient sun exposure in spring and summer time will allow you to get the annual norm of this vitamin.

  1. Eat foods rich in vitamin D. Although a normal diet cannot fully meet the body's vitamin D needs, try to eat foods that contain large number this vitamin. The best natural source Vitamin D sources include fish, including salmon, mackerel, tuna and sardines. In addition, you can drink fish oil, if you tolerate it normally. Small amounts of vitamin D are also found in egg yolks and cheese.

    Choose fortified foods. As we understand the benefits of vitamin D, everyone more companies add it to various foods. Pay attention to the composition of products and check whether they are fortified with vitamin D. Most often, this vitamin is added to milk and breakfast cereals.

    Limit your caffeine intake. Research has shown that caffeine can interfere with vitamin D receptors and interfere with its absorption. For this reason, caffeine can reduce calcium levels in the body, since vitamin D helps calcium absorption. Avoid drinking too much caffeinated drinks such as coffee, tea, and caffeinated sodas.

    • Try to eat foods with vitamin D not in the morning, along with morning coffee or tea, but at a later time, such as lunch.

  2. Follow all the recommendations above. There is no one universal method, which would provide the body with the amount of vitamin D it needs. Research shows that dietary supplements are a less effective source nutrients, how natural products, however, the diet is not able to provide the body with a sufficient amount of vitamin D. At the same time, the only reliable source of vitamin D - sunlight - is very dangerous in large quantities and can cause skin cancer. Best approach is to combine all three methods: nutritional supplements, exposure to sunlight and proper diet.

    Be aware of the risks of vitamin D deficiency. Every effort should be made to increase vitamin D levels in the body, since its deficiency contributes to the development of a variety of chronic diseases. It has been shown that low level vitamin D may lead to the development of type 1 diabetes, chronic pain in muscles and bones, as well as various types cancer, including cancer of the breast, rectum, prostate, ovary, esophagus, and lymphatic system.

    Find out if you have enough vitamin D. While 40–75% of people do not get enough vitamin D, some are especially susceptible to vitamin D deficiency. You should know the risk factors so that you can take appropriate measures, if necessary, to help increase your vitamin D levels in your body. The following people are at risk:

    • people with Gunther's disease (chronic photosensitivity) - they do not tolerate sunlight well;
    • those who rarely leave the house;
    • people with a fear of sunlight;
    • those who are due to malnutrition have increased sensitivity to light;
    • infants who are exclusively breastfed;
    • patients with impaired fat absorption;
    • those who constantly wear closed clothing;
    • older people whose skin perceives sunlight less well;
    • people who are indoors daytime, for example, nurses and so on;
    • some people with strict dietary restrictions.

  3. Get tested for vitamin D deficiency. A blood test to detect vitamin D deficiency is also called a 25(OH)D, or calcidiol, test. A blood sample will be taken from you and analyzed in a laboratory.

    Make sure your vitamin D levels stay within recommended limits. When you receive your vitamin D deficiency test results, you need to interpret them and make appropriate lifestyle changes. Test results are expressed in concentration units nmol/L (nanomoles per liter) (or ng/ml (nanograms per milliliter) in the US). This corresponds to blood levels of calcidiol, which is a reliable indicator of vitamin D levels in the body.

  • In order for the skin to produce the daily requirement of vitamin D, it is enough to be in the sun for 30 minutes a day.
  • Be careful when children are in the sun, especially younger age. Children should be exposed to the sun regularly, but additional safety precautions should be taken, including wearing hats and long sleeves.
  • Expose yourself to the sun in the late afternoon when you can do without sunscreen. To get rid of the cream, you will have to take a shower. However, it is convenient, for example, if you play sports after work.
  • If you live in an area where there is little sunny days, or you spend most of your time outdoors dark time day, take vitamin D3 supplements. The recommended daily dose is 4000–8000 IU (international units). Before taking any dietary supplements that exceed 2,000 IU, consult your physician.

Warnings

  • If the sky is completely overcast, the energy ultraviolet radiation reduced by 50%; in the shade (or with heavy smog) this energy is reduced by 60%, but this does not mean that solar radiation becomes completely safe, especially for people with hypersensitivity to the light. Even so, the portion of ultraviolet radiation that is transmitted by clouds can cause skin burns. Mid-wave ultraviolet radiation (ultraviolet B) does not pass through glass, so vitamin D is not produced by sunlight entering through a window.
  • Vitamin D is fat-soluble, so overdosing is possible. This is true for everyone fat-soluble vitamins, which include vitamins A, D, E and K. The maximum daily dose of vitamin D should not exceed 10,000 IU.
  • Among other things, vitamin D deficiency can lead to the following health problems:
    • Vitamin D deficiency syndrome, also known as rickets. Rickets involves softening of the bones in children, which can lead to fractures and bending. Rickets can cause severe vomiting and diarrhea, which leads to rapid elimination from the body of vital microelements.
    • IN possible consequences Vitamin D deficiency also includes dental problems, muscle weakness, frequent fractures of weak bones, bowed legs, deformity knee joints, curvature and deformation of the main bones in the skull, pelvis and spine, lack of calcium, which can lead to osteogenesis imperfecta(disturbances in the process of bone formation).
    • Violation mental health, such as depression or Alzheimer's disease.

Vitamin D is important for nervous system, regulates the concentration of phosphorus and calcium in the blood, controls the production of insulin by the pancreas, improves immunity and has a positive effect on the production immune cells, […]

Vitamin D is important for the nervous system, regulates the concentration of phosphorus and calcium in the blood, controls the production of insulin by the pancreas, increases immunity and has a positive effect on the production of immune cells, reduces the risk of cancer, treats psoriasis, promotes normal absorption of calcium and magnesium, strengthens bones and teeth. This post is dedicated to the properties and uses of vitamin D, such information is useful to everyone.

What is vitamin D?

Vitamin D is commonly called special biologically active substances. This group includes ergocalciferol (vitamin D2) - the body is saturated with it exclusively through food. And ergocalciferol (vitamin D3) - a person gets it from food, and the substance can also be spontaneously produced in the skin under the influence of ultraviolet radiation.

What is vitamin D for?

Ergocalciferol and cholecalciferol perform a number of tasks in the body. The main activity of these substances, which are similar in structure and action, is the regulation of the absorption of phosphorus and calcium during the movement of food along the small intestine. Most of these trace elements are absorbed in the duodenum.

Scientists have found that vitamin D is involved in the production of certain hormones, regulation of metabolism and the process of cell renewal. Valuable vitamins from group D are an important component of our diet. Every day the human body aged 1-70 years needs cholecalciferol in a volume of 15 mcg. Converted to international units, this is 600 IU. The same need occurs during pregnancy and breastfeeding.

Studies have shown that vitamin D is an effective prophylactic agent for the prevention of cancer processes in the mammary glands, prostate gland, and large intestine. When used correctly, the substance helps to avoid dangerous conditions, such as depression, obesity and heart disease, and also reduces the likelihood of respiratory diseases.

The fat-soluble substance calciferol is optimally absorbed along with fats in the intestines. All fat-soluble vitamins can be deposited in adipose tissue. Vitamin D in the human body can accumulate in such a volume over the summer that these reserves will be systematically spent during all the cold months of the year.

Vitamin D is also known to promote absorption important microelement magnesium and vitamin A.

Blood test for vitamin D

To determine the amount of vitamin D in the blood, venous blood is taken for analysis. Thus, you can quickly make a diagnosis of hypovitaminosis or hypervitaminosis. Such an analysis in mandatory donated by patients who have serious problems with bones - osteopenia, osteoporosis. Based on the results, doctors adjust treatment.

A doctor may prescribe a vitamin D test if there are complaints of bone deformation and rickets, growth arrest, repeated fractures, and bone pain. Also, a blood test may be required in case of digestive disorders, inaccessibility to sunlight, before bone surgery and dental implantation.

Let's give an approximate breakdown of the results of a blood test for vitamin D:

  • the normal test result is 30-100 ng/ml or 75-250 nmol/l;
  • a slight deficiency is indicated by a result of 10-30 ng/ml or 25-75 nmol/l;
  • a critical deficiency can be judged when the result is below 10 ng/ml or below 25 nmol/l.

The results of vitamin D tests are assessed by an endocrinologist and a surgeon. Along with this, a number of other examinations may be prescribed to clarify the picture. Typically, vitamin D reserves in the analysis are reduced due to a lack of vitamin E in the body, kidney and liver failure, little contact with sun rays, consumption of foods poor in vitamin D, taking certain medications.

Vitamin D in foods

Let's list the foods that contain the most vitamins of group D - vitamin D2 and D3. The values ​​given are per 100 g of product:

  • fish oil made from cod liver - 250 mcg (1667% of the average daily requirement);
  • canned cod liver- 100 mcg (667%);
  • high-fat herring fish - 30 mcg (200%);
  • canned oil sprats - 20.5 mcg (137%);
  • chum fish - 16.3 mcg (109%);
  • mackerel fish - 16.1 mcg (107%);
  • salmon (Atlantic salmon) - 11 mcg (73%);
  • pink salmon fish - 10.9 mcg (73%);
  • black granular caviar- 8 mcg (53%);
  • yolks from chicken eggs- 7.7 mcg (51%);
  • tuna fish - 5.7 mcg (38%);
  • chanterelle mushrooms - 5.3 mcg (35%);
  • morel mushrooms - 5.1 mcg (34%);
  • perch fish ( river fish) - 3 mcg (20%);
  • red granular caviar - 2.9 mcg (19%);
  • flounder fish - 2.8 mcg (19%);
  • pike fish - 2.5 mcg (17%);
  • perch fish (sea fish) - 2.3 mcg (15%);
  • chicken eggs - 2.2 mcg (15%);
  • ghee - 1.8 mcg (12%);
  • unsalted sweet butter - 1.5 mcg (10%);
  • quail eggs, goat milk, butter - 1.3-1.4 mcg (10%);
  • pollock fish and 50% cheeses (Swiss and cheddar) - 1 mcg (7%);
  • cod fish, 50% cheeses (Roquefort and Russian), 45% cheeses (Poshekhonsky and Dutch), Camembert cheese - 0.8-0.9 mcg (6%);
  • oyster mushrooms, Suluguni and Russian processed cheeses - 0.7 mcg (5%);
  • processed sausage and Adyghe cheeses, fat 18% cottage cheese - 0.6 mcg (4%);
  • feta, gouda, parmesan cheeses, shiitake mushrooms - 0.4-0.5 mcg (3%);
  • medium fat cottage cheese 9%, powdered milk with a fat content of 25% - 0.2-0.3 mcg (2%);
  • 10-35% cream, 2-5% cottage cheese, 20-30% sour cream, champignon and porcini mushrooms - 0.1-0.2 (1% daily requirement).

For convenience, the products in the list are arranged in descending order of vitamin D content per 100 g (and in descending order of percentage of the daily requirement). At the top of the list are the richest food sources that are recommended to be consumed in case of vitamin deficiency or to prevent it. The foods at the end of the list have minimal concentrations of vitamin D, but are still healthy.

Vitamin D norm

It is important to know not only what vitamin D contains, but also what the daily norms of calciferol are for different people. These data are shown in the table. table: daily norm vitamin D for different people

It is believed that taking a 20-minute sunbath can partially cover the need for vitamin D. It is necessary to stay outside in open clothes sleeveless. In this case, you need to get only half the daily requirement from products.

Who needs vitamin D most?

The body requires increased doses of vitamin D in the following cases:

  • period of active growth of children;
  • menopause in women;
  • bearing and breastfeeding a child;
  • rare walks in the sun;
  • old age.

As you can see, vitamin D for adults and children is necessary for the body to function properly. Deficiency and excess are extremely dangerous.

What can cause vitamin D deficiency?

IN following states Vitamin D stores are usually depleted, so additional doses are required:

  • improper food system, poor in fish and dairy products;
  • taking antacids;
  • pregnancy, breastfeeding;
  • age from 50 years;
  • renal and hepatic disorders;
  • vegetarian food system.

Symptoms of Vitamin D Deficiency

If there is a catastrophic lack of vitamin D in the body, ailments develop:

  • osteomalacia (as calcium is washed out, bone tissue liquefies);
  • sleep disorders;
  • osteoporosis;
  • low performance;
  • fatigue;
  • poor appetite;
  • poor health in general;
  • blurred vision;
  • burning in the larynx;
  • sluggish healing and recovery from fractures.

How does excess vitamin D manifest?

Note that overloading the body with vitamin D is a rare phenomenon; it can develop due to drug abuse:

  • breathing complications;
  • loss of appetite;
  • convulsions;
  • itchy skin;
  • surges in pulse and blood pressure;
  • headache and body weakness;
  • abnormal stool, vomiting, nausea.

Popular vitamin D preparations

Medicines are used as prescribed by a doctor and in strict compliance with the instructions. The following drugs are in demand today:

  • preparations based on colecalciferol - Aquadetrim drops and Vigantol oil solution;
  • preparations based on alfacalcidol - Alpha-D3-Teva capsules, intravenous solution, Etalfa capsules and drops, Alfadol capsules, Oksidevit oil solution, Van-Alfa tablets;
  • preparations based on paricalcitol - intravenous solution and Zemplar capsules;
  • a preparation based on colecalciferol, calcium carbonate and alendronic acid - Ostalon-Calcium-D tablets;
  • preparations based on calcitriol - Rocaltrol and Osteotriol capsules;
  • a drug based on alendronic acid and alfacalcidol - Tevabon capsules and tablets;
  • A natural source of vitamin D is an oil solution of fish oil.

Vitamin D in tablets and other forms should not be taken without consulting a doctor.

Vitamin D is important for athletes

People with elevated physical activity must take care of themselves, provide their body with microelements and vitamins in a timely manner.

Why vitamin D is necessary when playing any sport:

  • bone strengthening factor - if there is not enough vitamin D, then the body cannot absorb enough calcium, and the bones become fragile, which is detrimental to the athlete;
  • muscles work much better - deficit threatens muscle weakness and the development of muscle atrophy;
  • vitamin D saves from cardiovascular pathologies, unexpected heart attack, hypertension, which is certainly good during heavy physical activity;
  • reduces the risk of type 2 diabetes and cancer.

Effective sources of vitamin D for athletes include moderate sun exposure, good food and healthy nutritional supplements.

The importance of vitamin D for women

Women's health depends on lifestyle and nutrition. Vitamin D is of enormous importance for women. This fact is confirmed by the following observations:

  • with vitamin D deficiency, women develop severe depression and apathy towards everything, and feel a loss of strength;
  • due to a lack of vitamin D, problems with procreation occur - it is not possible to conceive a child;
  • vitamin deficiency is one of the risk factors for the development of obesity and diabetes;
  • with a lack of vitamin D, muscle weakness is a concern;
  • Vitamin D deficiency is inextricably linked with a high likelihood colds and virus infections.

Vitamin D for infants

  • promotes the accumulation of phosphorus and calcium reserves in bone and dental tissue;
  • supports normal development muscle tissue And correct height bones;
  • strengthens the immune system, which means it helps protect against a huge number of diseases;
  • rickets warns.

Children's vitamin D preparations:

  • Aquadetrim;
  • Osteotriol;
  • Alpha-D3;
  • Vigantol;
  • Fish oil;
  • Colecalciferol;
  • D3-Devisol-Drops.

The dosage is selected by the doctor individually, depending on the state of health.

It is important that the percentage of vitamin D in the diet is influenced by environmental factors. This vitamin breaks down under the influence of air and light. It is interesting that vitamin D does not disappear during heat treatment, since it does not change when heated. It is believed that vitamin D reserves can be replenished by being outside in sunny weather. But it should be noted that sunscreens hinder the production of vitamin D in the skin by 90%. And yet it is dangerous to sunbathe without SPF cream, it threatens early aging and skin cancer. Therefore, the issue of sunbathing must be resolved wisely.

Vitamins are a group of biologically active organic compounds, vital for any living organism. One of the most important vitamins for humans is vitamin D, which exists in several forms. The two main forms of this vitamin are ergocalciferol (D 2) and cholecalciferol (D 3). The latter compound is synthesized in the human body under the influence of sunlight, but can also be supplied with food. Ergocalciferol is only available from food sources.

Physico-chemical properties

The chemical formula of vitamin D (ergocalciferol) is C 28 H 44 O, cholecalciferol is C 27 H 44 O. Vitamin D is a fat-soluble substance: in the body this compound is converted into a hormone that takes an active part in the metabolism of calcium and phosphorus and regulates many others processes of intracellular and tissue vital activity.

The substance was discovered in 1922: the American E. McCollum proved the relationship between a disease such as rickets and a deficiency of this vitamin in the body. This was the fourth vitamin discovered by science, which is why it was named the fourth letter of the Latin alphabet - D. A little later, the possibility of obtaining vitamin D from sunlight was proven. In the United States, the practice of ultraviolet irradiation of dairy products in order to increase their cholecalciferol content has become widespread.

Both forms of vitamin D are, in fact, provitamins. To activate its beneficial properties for humans, the compound must be transformed by liver enzymes into a hormone called calcitriol. It is in this form that the vitamin is of greatest value to physiological processes occurring in the body.

The role of vitamin D in the body

The main function performed by vitamin D is the regulation of metabolic processes of phosphorus, magnesium and calcium in the blood. The condition of teeth and skeletal system, skeletal strength and stability, muscle strength.

In addition, vitamin D:

  • Stimulates the processes of calcium absorption in the intestines and kidneys;
  • Takes direct part in the processes of cell growth and development;
  • Protects the human body from development malignant neoplasms, preventing the pathological division of cells of the skin, intestines, ovaries, prostate and mammary glands;
  • Effective in preventing leukemia - serious illness bone marrow(the disease is sometimes not entirely correctly called “blood cancer”);
  • Playing important role in the functioning of the immune system: the amount of vitamin directly determines the functionality of that part of the bone marrow that is responsible for the production of monocytes - immune cells;
  • Regulates the production of insulin in the pancreas;
  • Ensures stable functioning of the nervous system, influencing calcium levels: thus, full transmission occurs nerve impulses to the muscles;
  • Provides recovery containment shells nerve, preventing the development of multiple sclerosis;
  • Takes part in the processes of blood coagulation and regulation of vascular pressure;
  • Stimulates the functioning of the thyroid gland.

Vitamin D affects the condition of human skin, muscle tissue, bones and prevents rickets caused by calcium deficiency, which cannot be fully absorbed due to cholecalciferol deficiency. The compound is used in medicine in the treatment of cancer and is part of drugs that increase the life expectancy of AIDS patients.

Units of measurement and daily dosages

The amount of vitamin is usually calculated in international units of measurement (IU). 1 IU is equal to 0.025 μg of cholecalciferol or ergocalciferol. Vitamin D can be obtained from any source, be it sunlight, which affects the production of vitamin in the body, foods or vitamin preparations. Depending on age, a person’s need for vitamin D is as follows:

  • Children under 13 years old - 200-400 IU;
  • Teenagers and adults under 50 years old - 200-250 IU;
  • People from 50 to 70 years old - 400 IU;
  • Elderly people over 70 years old - 600 IU.

Shortage

If a person is regularly exposed to ultraviolet radiation, he does not become deficient in vitamin D 3. D2 deficiency can occur with insufficient and poor nutrition. Vitamin D hypovitaminosis most often occurs in older people who spend most of their time at home and are rarely exposed to sunlight. Vitamin D in such people ceases to be produced.

25% of elderly patients constantly hospitalized suffer from vitamin deficiencies - they develop osteoporosis and other bone pathologies. Pregnant women, nursing mothers, and residents of the Far North are also at risk.

Despite sun exposure, in some cases the body may produce limited amounts of vitamin D due to factors such as:

  • Light wavelength (the mid-wave spectrum is more effective, which can be obtained in the morning and evening, at sunset);
  • Skin pigmentation (the darker the skin, the less vitamin is produced);
  • Age (aging skin gradually loses its ability to synthesize cholecalciferol);
  • Air pollution (dust and emissions industrial production block some of the rays of the ultraviolet spectrum: these explain the prevalence of rickets among African children living in large cities).

In adults, vitamin D deficiency manifests itself (in addition to bone dysfunctions) increased fatigue, depressed mood, a tendency to fractures with little load on the skeleton, difficult regeneration of bone tissue due to their demineralization, weight loss and deterioration of vision.

IN childhood Lack of cholecalciferol causes rickets - underdevelopment of the skeletal system.

The symptoms of this disease are as follows:

  • Slowing down the process of teething and closure of the fontanel;
  • Softening flat bones skull, flattening of the back of the head, formation of layers in the area of ​​the parietal and frontal tubercles (the so-called “Socrates’ head”);
  • Deformation of facial bones;
  • Curvature lower limbs and pelvis (“flat pelvis”);
  • Chest transformation;
  • Sleep disturbance increased sweating, tearfulness, irritability.

A measure to prevent rickets is taking vitamins (at a dosage of 1500 IU per day) during pregnancy. You can also take natural or pharmacy fish oil in the amount of 1.5-2 tbsp. spoons daily.

Oversupply

IN in good condition Vitamin D does not create an excess in the body and is synthesized in it depending on current needs. occurs when using inadequate medicinal doses or long-term treatment with drugs containing this vitamin.

Severe D-hypervitaminosis (overdose) causes symptoms such as:

  • Weakness, nausea, vomiting, intestinal disorders(constipation and diarrhea);
  • Loss of appetite;
  • Headache, joint and muscle pain;
  • Fever, hypertension, seizures;
  • Asphyxia (suffocation);
  • Slowing heart rate.

Long-term use of medications containing vitamin D in excess amounts can lead to resorption bone tissue and the occurrence of osteoporosis. Calcification of blood vessels and heart valves may develop. Excess calcium can also be deposited in the lungs and intestines, leading to dysfunction of these organs and the development of polyuria (excess urine production) and arthralgia (joint damage).

Vitamin D is found in many foods, but the “champions” in terms of its content are:

  • Fish oil is the best food source of the vitamin (1 tablespoon contains 300% of the recommended daily dose);
  • Salmon: the fats contained in this fish are rich not only in vitamin D, but also in other essential microelements (vitamin D is also found in tuna, sardines and mackerel);
  • Milk (cheese and other dairy products) - one glass contains 25% of the daily value;
  • Cereals;
  • Forest mushrooms;
  • Eggs - Vitamin D is found in egg yolks;
  • Orange juice;
  • Beef liver;

Vitamin D is relatively resistant to heat treatment.

You can get the required dose of cholecalciferol by regular visits solarium. The amount of ultraviolet radiation necessary for the synthesis of vitamin D does not penetrate through glass, fabric and sunscreen. IN winter time Residents of northern latitudes may experience a constant deficiency of the vitamin, so they should replenish the necessary reserves by obtaining the compound from food.

Interaction

The level and synthesis of vitamin D in the body can be negatively affected by the following factors:

  • Taking medications that reduce cholesterol (these drugs interfere with fat absorption);
  • Taking corticosteroids;
  • Use of barbiturates;
  • Taking certain medications for tuberculosis;
  • Use of laxatives.

Dosage forms

Preparations containing cholecalciferol and ergocalciferol are available in the form of tablets, capsules with a soluble shell, oil solutions and drops for oral administration. D 3 is also included in many vitamin complexes For general strengthening body.

The required dosage of drugs is prescribed by the attending physician..

Residents of northern latitudes, children and the elderly should pay special attention to the presence of the required amount of vitamin D in the body. Additional reception vitamin should be taken under medical supervision. Use D 2 and D 3 in dosage form should be used with caution in people with kidney disease and cardiovascular problems.

Vitamin D, also called calciferol, is essential for people of all ages. The substance must be regularly supplied to the body in order for the skeleton to remain strong. Calciferol is extremely important for older people prone to pathologies of the musculoskeletal system. The vitamin is synthesized in the skin under the influence of sun radiation and also enters the body with food. Therefore, it is important for both adults and children to eat well and take frequent walks in the sun. If hypovitaminosis has developed, it is recommended to take vitamin D tablets.

The benefits of calciferol for the human body

Vitamin D performs several important functions in the human body:

  • participates in the metabolism of calcium and phosphorus;
  • moves minerals through the bloodstream into bone tissue;
  • helps strengthen the immune system;
  • regulates the absorption of mineral elements in the intestines;
  • participates in the production of certain hormones.

There are several types of calciferol:

  • D 2 – ergocalciferol;
  • D 3 – cholecalciferol;
  • D 5 – sitocalciferol;
  • D 6 – stigmacalciferol.

Each of the above types of calciferol performs human body its function. Vitamins D2 and D3 are especially important for humans. Other types of calciferol do not have a significant effect on the functioning of organs and systems.

Cholecalciferol is necessary for the complete absorption of calcium and phosphorus in intestinal tract. Ergocalciferol optimizes the concentration of minerals in bone tissue. Vitamins D 2 and D 3 work in combination, so they both must enter the body in optimal quantities.

The effect of vitamin D on the female and male body

Vitamin D deficiency is the main enemy female beauty. Calciferol maintains healthy bone structure, normalizes the functioning of the heart muscle and nerve fibers, regulates metabolism and blood clotting processes. If there is a lack of the substance, women's nails break, hair falls out profusely, gums bleed and teeth decay, limbs hurt, and fractures are often observed. The vitamin is also responsible for the absorption of phosphorus. With calciferol deficiency in women, due to a decrease in phosphorus in the body, skin rashes, your health worsens, you feel aching in your bones, your metabolism is disrupted.

Men with vitamin D deficiency experience the same health problems as women. In addition, calciferol is important for maintaining normal hormonal levels V male body. When there is a lack of the substance in men, the concentration of testosterone in the blood decreases, which increases the effect of female sex hormones on the body.

Daily intake of calciferol

The amount of vitamin consumed per day depends on age and physical condition person.

  1. For adults, the norm is 400 IU per day.
  2. For children and adolescents - from 400 to 600 IU.
  3. For older people - from 600 to 800 IU.
  4. For pregnant women - about 800 IU.

The best way to get vitamin D is to stand in direct sunlight. People who rarely go outside or live in northern regions have a significantly increased risk of developing hypovitaminosis D. The following categories of people need calciferol the most:

  • inhabitants of high latitudes;
  • residents of industrial areas where the air is heavily polluted with harmful substances;
  • workers forced to work night shifts;
  • vegetarians, adherents of strict diets;
  • old people;
  • dark people, skin which poorly receive solar radiation;
  • people with reduced immunity or serious illnesses.

Indications for use of vitamin D

Vitamin D 3 is prescribed for the prevention and treatment of the following pathologies:

  • rickets in children - a disease accompanied by thinning of bone tissue and skeletal deformation due to impaired calcium metabolism in the body;
  • osteoporosis;
  • deterioration in the functioning of the immune system, accompanied by respiratory dysfunction and chronic fatigue;
  • oncology, if there is a predisposition to the development of malignant tumors;
  • eczema, psoriasis and other skin diseases;
  • hypocalcemia;
  • renal tubular acidosis.

Vitamin D is also often prescribed as a restorative after long-term use corticosteroid and anticonvulsant medications.

People living in the northern regions must periodically take calciferol preparations to prevent hypovitaminosis and other serious pathologies. For preventive purposes, the vitamin is prescribed at least once every three years.

Calciferol-rich foods

Solar radiation is the main, but not the only source of vitamin D. In the winter months, when there is a lack of sun, it is recommended to consume foods containing significant amounts of calciferol. The list of these products includes:

  • fish oil;
  • sea ​​fish;
  • cheeses;
  • butter;
  • yolk;
  • milk.

List of the best vitamin D tablets

Sold in pharmacies a huge number medicines based on vitamin D, both cheap and expensive. The price is determined by the form of release of the medicine, effectiveness, cost, active substance. Thus, drugs based on vitamin D 3 are more expensive than drugs containing vitamin D 2.

  1. .The best drug, assigned to the frail and premature babies. For infants, the vitamin is given in drop form. One drop contains 600 IU of calciferol. To give medicine to a child, the drop must be dissolved in small quantity water. Aquadetrim is also prescribed to children and adolescents to prevent rickets.
  2. Alpha D 3 -Teva. The medication is sold in capsules containing a solution of calciferol in oil. Intended for adults and children over 6 years old. The medication is taken daily, after meals you need to swallow 1 - 2 capsules with enough water. According to the instructions for use, the capsule should be swallowed without chewing.
  3. Calcium-D 3 Nycomed. Chewable fruit tablets containing optimal amounts of cholecalciferol and calcium. The drug is intended for adults and children over 6 years of age. The recommended dosage is one tablet per day. The tablet is dissolved or chewed after eating.
  4. Vitrum Calcium + Vitamin D 3.Complex drug, sold in tablet form, intended primarily for the prevention of osteoporosis. Optimal dosage– one tablet 2 times a day. The medication is taken before or during meals. It is better not to chew the tablet, but to swallow it whole.
  5. Tevabon. The medicine is sold in tablet form and capsule form. Prescribed for the treatment of osteoporosis. The active ingredient is alfacalcidol. This synthetic analogue vitamin D.
  6. . A complex preparation based on calcium and cholecalciferol. Recommended for women as it eliminates brittle nails. It also improves the absorption of minerals in the body, prevents the development of osteoporosis, and normalizes blood clotting. You need to take 1-2 tablets a day, preferably chew them.
  7. .Medicine in tablets, designed specifically to eliminate osteoporosis and rapid skeletal regeneration after fractures. The components of the drug are cholecalciferol, calcium, copper, zinc, boron.
  8. Calcemin. Biologically active additive, containing calcium, cholecalciferol, zinc, manganese, copper. You need to take 1 tablet per day.
  9. Natekal D 3.Chewable tablets based on calcium and vitamin D 3. The medication provides the body with an optimal amount of mineral and helps normalize hormonal levels. Daily dose– 1 – 2 tablets. Reception is carried out after meals.
  10. Etalfa. A high-quality Danish drug is sold under this name. Available in drop and capsule form. The vitamin in capsules is dissolved in sesame oil. The medication is intended for the treatment of rickets and osteoporosis.
  11. Van Alpha. A drug in tablet form based on alfacalcidol, an artificial analogue of vitamin D. It is prescribed for the treatment of rickets, strengthening the immune system, and normalizing the functioning of the thyroid gland.

Overdose and side effects

If a person is insensitive to the substance, takes the drug in accordance with the instructions, then side effects usually not observed. IN in rare cases noted:

  • nausea;
  • headaches;
  • diarrhea;
  • deterioration of kidney function.

In case of sensitivity to the substance or overdose, the following symptoms are observed:

  • sudden weight loss;
  • nausea, vomiting;
  • constipation;
  • dehydration;
  • calcification;
  • increased blood pressure.

Contraindications to the use of vitamin D

Like all other vitamins, calciferol should not be taken in excess. People who are sensitive to vitamin D should not take vitamin D supplements. active component suffering from renal osteodystrophy and urolithiasis. People with tuberculosis, heart pathologies, kidney and liver disorders, stomach ulcers, or duodenum. Women during pregnancy and breastfeeding should definitely consult a medical specialist before taking a vitamin D supplement.