Vitamin D - biological functions, consumption rate, symptoms of deficiency and excess. Instructions for using vitamin D. Solar vitamin: time to get and accumulate

Greetings, friends! Summer is coming to its logical conclusion and I decided to extend it with my articles. Let's answer this question: "What do we know about vitamin D?" In the modern philistine view, this is a substance that children need so that there is no rickets - a severe violation of calcium-phosphorus metabolism.

Is it only this, undoubtedly important, role that the solar vitamin plays? Today, your understanding of this substance will change once and for all. Let's start!

Biochemistry of Vitamin D

And I want to start a little with the biochemistry of vitamin D: where it is synthesized, what stages of metabolism it goes through.

Our mothers and grandmothers drove us to the street so that we could be more on fresh air under the sun. And not in vain! After all, they knew that under the influence sun rays, namely the UV-B spectrum with a wavelength of 290-315 nm, a very valuable vitamin is synthesized in the skin, which protects against the pathology of the bone and muscle systems.

Indeed, cholecalciferol (Vitamin D3) is synthesized in the skin from a substrate called 7-dehydrocholesterol (read cholesterol). After that, this form of vitamin binds to a carrier protein and rushes into the bloodstream (see photo above). In addition, not a large number of comes with food.

Further, in the liver, cholecalciferol is converted by hydroxylation into the active metabolite 25-hydroxyvitamin D3, which is designated as 25 (OH) D3 or simply CALCIDIOL. It is by this laboratory marker that we look at whether there is enough vitamin D in the body.

The next step with the blood flow, this form of the vitamin enters the kidneys, where it undergoes another hydroxylation reaction and as a result a metabolite is formed with the complex name 1,25-dioxycholecalciferol or 1,25 (OH) 2D3 or simply CALCITRIOL.

This is the most active and most unstable form of vitamin D. It is due to this metabolite that all its biological effects are realized. Calcidol binds to its carrier protein (VDBP) and is carried throughout the body to do good deeds.

Biological effects of solar vitamin

The effects of vitamin D are divided into:

• Genomic
• Extragenomic

Impact on genes

Almost every cell in our body has a special docking site for vitamin D on its surface - this is the VDR receptor. The receptor has two domains that bind to the vitamin and the cell's DNA.

Yes, it's not a typo. The uniqueness of vitamin D is that, through its receptor, it immediately acts on cellular DNA, giving a signal for the implementation (expression) of a particular gene.

Just think about this phrase: "Vitamin D regulates the DNA of every cell in the body." This is especially true for the tissues of the skin, large intestine and adrenal cortex.

There are special sections on DNA that react to the presence or absence of this important substance. They are called vitamin D-binding elements (VDRE).

When the active metabolite CALCITRIOL, which is 100 times more active than calcidiol, lands on its VDR receptor, this receptor immediately connects to the nuclear DNA, namely to separate sections DNA (VDRE) and the fun begins.

Processes that are programmed in a certain gene are launched, for example, the synthesis of a specific protein for some system, for example, the immune system. Vitamin D affects the levels of other hormones, growth and inflammation factors, numerous proteins, and, of course, calcium levels in the blood.

It has already been established and proven that vitamin D controls more than 200 genes, but it is also assumed that this number actually reaches 5000 genes. By the way, only 7-10% of the genes of the total number of genes controlled by Vit D are involved in the regulation of calcium in the blood.

So, if you thought that vitamin D is only responsible for the development of bones, then you are greatly mistaken; we were all greatly mistaken, since the spectrum of action of this substance is much wider and larger.

It is because of its mechanism that vitamin D is now considered not a vitamin at all, but a real hormone. Only hormones have the ability to influence how DNA works!

And recently it became known that this substance can have an epigenetic effect. The prefix "epi" means "above", that is, supragenetic influence. In other words, vitamin D can change the information recorded in our genes, that is, affect the genes by changing them.

This happens through processes complex names- DNA methylation, acetylation of DNA-stabilizing histone proteins and others. Maybe someday I'll try to talk more about it. not to miss.

Extragenomic effects

But vitamin-hormone D also has non-genomic mechanisms of action on the cell. As a rule, this is the control of the work of various enzymes in the cell matrix (adenylate cyclase, phospholipase, protein kinase, and others), the effect on mitochondria, and therefore active participation in the energy supply of cells.

What controls vitamin D

1. Calcium regulation, namely intestinal absorption and bone remodeling. With a deficiency, rickets, osteoporosis, osteomalacia develop.
2. Regulation cell cycle, i.e. so that the cell grows, develops and dies in time. Deficiency increases the risk of many types of cancer. oncological diseases, especially cancer of the prostate, breast, colon and rectum, leukemia.
3. Influence at immune system, namely the work of macrophages and the synthesis of antimicrobial peptides. Deficiency leads to frequent infectious diseases up to tuberculosis, and autoimmune disorders(type 1 diabetes, autoimmune thyroiditis, multiple sclerosis, psoriasis, ulcerative colitis and Crohn's disease and others)
4. Participates in the synthesis of insulin. Vitamin D deficiency leads to impaired insulin secretion, glucose tolerance and diabetes mellitus.
5. Regulation cardiovascular disease. If the vitamin is not enough, then high-renin (renal) hypertension develops, increased thrombus formation, the risks of heart disease, myocardial infarction in particular, increase.
6. Controls muscular system. Deficiency leads to various myopathies.
7. Affects the functioning of the brain. With a lack of vitamin during fetal development, the risk of behavioral disorders in adulthood is high, and in adults the risk of Parkinson's disease and mental degradation increases.
8. Participates in regeneration (wound healing, regulation of inflammation processes).

The listed list is a small fraction, which reflects the huge impact of vitamin D on the human body. There are actually many more effects, and some are so difficult to understand for a person far from medicine that I will not focus on this.

The purpose of today's article was to plant in your mind the value and super-importance of the solar vitamin-hormone D for human health. And it doesn’t matter how old you are, whether you have diabetes or not, and for a diabetic it is especially important to know, it also doesn’t matter what your initial level of health is, because this applies to every human being on the planet.

As you can see, I have long gone beyond diabetes in my articles. Now my recommendations are valuable and useful even for healthy person if he wants to live long and healthy. Today I open a series of articles that will be devoted to the "solar miracle".

Follow the news, check regularly email, wait for my articles, because further information will be even more useful, juicier and tastier. After a while, wait for an article about how much sun we have enough to make up for vitamin D deficiency.

Like the article, share with family and friends. Everyone should know this information! See you!

With warmth and care, endocrinologist Lebedeva Dilyara Ilgizovna

What is vitamin D?

Up until the mid-1990s, the answer to this question would have been fairly simple: Vitamin D is a fat-soluble vitamin needed to prevent a bone disease in children called rickets. Previous research since the early 1800s found that fish fat may help prevent and treat bone development problems in children. In the early 1900s, a compound called "fat-soluble factor D" was isolated from fish oil, and this factor turned out to be the vitamin we now call "vitamin D" (vitamin D). Further Scientific research rickets helped to establish the role of sunlight in the formation of vitamin D.

However, starting in the mid-1990s, our understanding of vitamin D began to change dramatically. It is no exaggeration to say that the last 15 years have revolutionized our understanding of this vitamin! We now know that vitamin D is not just a fat-soluble vitamin essential for bone health, it also functions as a hormone.
Hormones are found in most various types cells and they are responsible for regulating various physiological processes.

There are two main types of vitamin D:

Ergosterol(egosterol) is the main building block of vitamin D in plants. Under ultraviolet sunlight, the ergosterol of plant leaves is converted into ergocalciferol, or vitamin D2 ( vitamin D2).

Cholesterol(cholesterol) is the main building block of vitamin D in the human body. Just the same when ultraviolet radiation gets into our skin cells, one of the forms of cholesterol in our skin cells called 7-dehydrocholesterol can be converted into cholecalciferol, a form of vitamin D3 ( vitamin D3).

In plant life, ergocalciferol (a form of vitamin D2) serves most of its intended purposes. In human life, however, cholecalciferol (vitamin D3) is not the final form - further metabolism is required for the development and growth of our bodies.

Obtaining hormonal forms of vitamin D:

The first step involves converting cholecalciferol to hydroxyvitamin D, also called 25-hydroxyvitamin D or 25(OH)D. Hydroxyvitamin D can be formed in the liver, kidneys, lungs, skin, prostate, brain, on the surface blood vessels and macrophages of cells of the immune system. The formation of hydroxyvitamin D requires the enzyme CYP27A1.
The second step involves the conversion of hydroxyvitamin D to dihydroxyvitamin D (also called 1,25-dihydroxyvitamin D or 25(OH)2D). This second step can occur in the lungs, brain, liver, stomach, spleen, kidneys, colon, thymus, lymph nodes, skin, placenta and dendritic cells of the immune system. The formation of dihydroxyvitamin D requires the enzyme CYP27B1.

Vitamin D value or Vitamin D value

Vitamin D plays a radical role in many different aspects of our
health:

Vitamin D helps optimize calcium and phosphorus metabolism.
Vitamin D helps prevent type 2 diabetes (non-insulin-dependent diabetes), heart attack, congestive heart failure, and stroke.
Vitamin D prevents the causes of muscle weakness, helps regulate muscle composition and muscle activity.
Vitamin D helps prevent bone integrity and osteoporosis.
Vitamin D regulates the activity of insulin and.
Vitamin D plays important role in regulation immune response organism.
Vitamin D helps regulate blood pressure
Vitamin D reduces the risk of excessive inflammation and some bacterial infections.
Vitamin D supports cognitive functions and stabilizes mood, especially in older people, prevents chronic fatigue.
Vitamin D is essential in preventing the following types of cancer: Bladder, breast, colon, ovaries, prostate and rectum

The hormonal functions of vitamin D include regulating bone and muscle health (including both skeletal and cardiac muscle), regulating the immune response, regulating insulin and blood sugar, and regulating calcium and phosphorus metabolism.

More detailed information these functions are presented in the following paragraphs.

Vitamin D in the regulation of calcium and phosphorus for bone health.
The composition of bones includes many different substances, including collagen proteins, keratin proteins and various minerals: silicon, boron and. Two particularly important components of bones are the minerals calcium and phosphorus. These minerals make up the bulk of a substance called hydroxyapatite, which accounts for more than half of the bone composition.
Parathyroid hormone (PTH) in conjunction with vitamin D are the most important regulators of health bone tissue.
When blood calcium levels decrease, parathyroid hormone causes calcium to be released from our bones to raise blood calcium levels back to normal. Parathyroid hormone also acts on our kidneys to store more calcium (storing it in our blood) and excrete more phosphorus (thereby helping to create a more favorable ratio of calcium to phosphorus in the blood). If too many parathyroid hormones are produced parathyroid glands, too much calcium can be transferred from the bone into our bloodstream, resulting in damage to bone health and of cardio-vascular system. Studies have shown that vitamin D deficiency is one of the key factors in the risk of overproduction of parathyroid hormones.

Vitamin D in the regulation of immune function.
The role of vitamin D in the regulation of the immune function of the body is so great that it is almost impossible to study an autoimmune disease without taking into account possible role vitamin D. This statement is true for diseases such as rheumatoid arthritis, multiple sclerosis, Crohn's disease, systemic lupus erythematosus, and many other autoimmune conditions. Autoimmune conditions are an extremely active area of ​​vitamin D research.

Vitamin D in the regulation of blood pressure and cardiovascular disease.
Vitamin D plays a direct role in regulating our blood pressure by inhibiting the activity of the renin-angiotensin system. To help increase blood pressure when it gets too low, the renin-angiotensin system stores sodium and water in the body, thus providing more fluid to our blood vessels and causing our blood vessels to constrict and thereby increasing pressure within them. Optimal levels of vitamin D keep this system under control. Vitamin D deficiency is a significant risk factor for high pressure. During pregnancy, the risk of high blood pressure is associated with maternal vitamin D deficiency.
The role of vitamin D is not limited to the regulation of blood pressure. Vitamin D also plays a key role in the regulation of calcium metabolism.
Calcium overload of cells caused by vitamin D deficiency is a problem for cardiac tissue and increases the likelihood of developing oxidative stress and tissue damage. Efficiency of healing of heart tissue after heart attack directly depends on optimal level vitamin D.

Vitamin D regulates insulin activity and blood sugar balance.
There is no doubt that vitamin D is involved in the regulation of blood sugar and insulin metabolism, this mechanism has not yet been fully understood.
Vitamin D deficiency is a clear risk factor for the development of type 2 diabetes, and vitamin D levels are associated with insulin secretion from pancreatic beta cells.
Interestingly, with vitamin D deficiency, parathyroid hormone is secreted in large quantities, too much calcium accumulates in the cells. An excess of calcium in fat cells causes the cells to overproduce cortisol, a hormone that counteracts the effectiveness of insulin. In addition, too much calcium accumulation in our fat and muscle cells can inhibit the formation of the GLUT-4 carrier protein. This protein helps carry sugar (glucose) from our blood to our cells. Without enough vitamin D, too little GLUT-4 is formed, and there isn't enough insulin to do its job.

Vitamin D regulates muscle composition and activates muscle activity.
Research in this area has advanced greatly in the last ten years, and vitamin D has been shown to play a key role in preventing muscle weakness, especially in the elderly.
Interestingly, vitamin D deficiency is associated with too much fat accumulation in the body. muscle tissue thus, muscle strength is reduced and physical performance is compromised.

Vitamin D and cancer prevention.
The role of vitamin D in cancer prevention is not quite obvious, and work is being intensively carried out in this direction. However, studies have already shown the importance of vitamin D in the prevention of the following types of cancer: bladder cancer, breast cancer, colon cancer, ovarian cancer, and. In certain situations, vitamin D performs the function of anticancer agents and is used in the treatment of cancer.

Other benefits of vitamin D
Research into the effects of vitamin D on:
- Senile dementia and;
- Cognitive functions (impaired thinking), especially in aging individuals;
- Mood disorders, especially in the elderly;
- Related autoimmune diseases, such as .

Vitamin D norms

Recommended daily allowances for vitamin D (approved by the US National Academy of Sciences in 1997):
Children and teenagers: 5 mg
Men and women, under 50: 5 mg
Men and women, 51 to 70 years old: 10 mg
Men and women, aged 71+: 15 mg
Pregnant and lactating women: 5 mg

Vitamin D deficiency

Lack of sun exposure for any reason, including geographic location, use of sunscreen, or wearing protective clothing, may be the cause of vitamin D deficiency.

Vitamin D deficiency can cause:
Muscle pain and muscle weakness
Bone pain, frequent bone fractures, or softening of the bones
growth retardation in children, rickets
Asthma in children (especially severe)
Cognitive impairment, especially among the elderly
reduced immunity
Chronic lack of energy and fatigue
especially among the elderly
Autoimmune disorders

Excess vitamin D

Excessive intake of vitamin D can be toxic, and vitamin D toxicity can come with any form of plant (D2) or animal (D3) origin. Symptoms of intoxication include loss of appetite, nausea, vomiting, high blood pressure, and impaired kidney function. However, it is also important to note that a vitamin D deficiency for the vast majority of people is a much greater risk than an excess of vitamin D. An increase in vitamin D from food intake is extremely unlikely.

What medications affect vitamin D?

The use of these drugs can reduce the amount of vitamin D in the body:
Anticonvulsant drugs, including Dilantin, are used to control seizure activity in people with epilepsy and brain cancer, head trauma, or stroke. These drugs reduce the activity of vitamin D.
Cholesterol-lowering drugs (eg, probucol, cholestyramine, clofibrate, colestipol, and gemfibrozil). These drugs may decrease intestinal absorption of fat-soluble nutrients including vitamins A, D, E and K.
Cimetidine (Tagamet and Tagamet HB) limits education of hydrochloric acid in the stomach and is used to treat symptoms associated with the stomach and duodenum. This drug may reduce the accumulation of vitamin D in the liver.
substitution hormone therapy may increase blood levels of vitamin D.
Corticosteroids are a family of anti-inflammatory drugs, including hydrocortisone and prednisone, that are commonly used in the treatment of autoimmune and inflammatory diseases such as asthma, rheumatoid arthritis, and ulcerative colitis. These drugs reduce the activity of vitamin D.
Heparin, an anticoagulant used to prevent blood clots after surgery, may interfere with vitamin D activity.

Sources of Vitamin D

Foods richest in vitamin D: oily fish(salmon, sardines), shrimp, milk, cheese, cod liver, eggs, fortified milk. Wild salmon contains significantly more vitamin D than farmed fish.
human breast milk contains only a small amount of vitamin D.

Because dairy products are an important source of vitamin D in the United States, there is extensive research on the stability of vitamin D to temperature and storage conditions. Researchers have found that almost no loss of vitamin D is retained during pasteurization of processed cheeses under normal commercial conditions. They also found that about 25-30% of vitamin D is lost when the cheese is baked at 450°F (232°C) for about 5 minutes.
Studies show that foods (like pizza cheese) cooked in an oven at 400-450°F (204-232°C) for about 20 minutes lose at least one quarter of their vitamin D during the reheating process. This percentage of vitamin loss is still relatively low compared to similar loss of other vitamins (especially less thermostable vitamins like vitamin C).
Storing cheese over a 9-month period between 39-84°F (4-29°C) showed no loss of vitamin D and also highlighted the relative stability of this vitamin.

Nutritional supplements

The two forms of vitamin D used in dietary supplements are: ergocalciferol(vitamin D2) and cholecalciferol(vitamin D3).
Ergocalciferol is sometimes considered a vegetarian source of vitamin D because it plant origin. However, yeast is also widely used as a source of D2, as are other fungi (eg ergot).

Cholecalciferol (a form of vitamin D3) can be obtained from animal or microbial sources. In practice, D3 was found in sheep's wool. Sheep (and many other animals) have sebaceous glands in the skin, which secrete a complex of various substances, including cholesterol (in the form of 7-dehydrocholesterol).
The most common form of vitamin D3 is a gel capsule containing D3 in liquid form (and often dissolved in linseed oil or olive oil). D3 is also available in powder form, D3 capsules, compressed tablets, and liquid form (D3 drops).

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 poor in it. In fact, the richest source of this vitamin is sunlight, but prolonged exposure to the sun is harmful to the skin. Maintaining adequate levels of vitamin D can be challenging. Nonetheless, proper diet nutrition, judicious use of sunlight, and intake recommended by a doctor food additives help you make sure your body gets enough of 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 can provide it. In view of this, it is impossible to provide your body with sufficient amounts of vitamin D through diet alone. You should not only include foods rich in this rather rare vitamin in your diet, but also take nutritional supplements with it. Vitamin D supplements are available in two forms: vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol).

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

Carefully increase your time in the sun. Although vitamin D is not commonly found in foods, it is produced in the body by exposure to sunlight. However, you should strike a balance and not be in the sun for 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 on the face. You can also sunbathe for 2-3 minutes several times a week and also apply sunscreen only on your face. In any case, you should not bathe within an hour of being in the sun.

Be aware of factors that can affect vitamin D production from sunlight. One of them is geographic latitude - the closer you live to the equator, the more solar radiation you will receive. In addition, the natural color of the skin affects the production of vitamin D: due to less melanin pale skin produces more of this vitamin than a darker one.

• Although some factors are difficult to change, you can choose what time of day to go out in the sun. Choose a time around the middle of the day, not in the morning or evening. In the middle of the day, solar radiation is most intense, which contributes to the release of more vitamin D.
• Open up to the sun as much as possible about larger areas of skin. During those few minutes when you are intentionally lying in the sun, do not wear closed clothes with long legs and sleeves! The more area of ​​skin exposed to sunlight, the more vitamin D your body will produce. However, be careful. If you live in a region with very bright sunlight, be careful not to get sunburned.
• Remember that sunlight is quite intense even on cloudy days.
• The human body stores vitamin D, so sufficient sun exposure during spring and summer will allow you to get the annual amount of this vitamin.

1. Eat foods rich in vitamin D. While a normal diet may not be able to fully meet your vitamin D needs, try to eat foods that are high in this vitamin. the best natural source vitamin D is fish, including salmon, mackerel, tuna and sardines. You can also drink fish oil if you can tolerate it well. Small amounts of vitamin D are also found in egg yolks and cheese.

   Choose fortified foods. As the benefits of vitamin D are understood, more companies are adding it to their diets. various products nutrition. Pay attention to the ingredients of foods and check if they are fortified with vitamin D. This vitamin is most often added to milk and breakfast cereals.

   Limit your caffeine intake. Studies have 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, as vitamin D promotes calcium absorption. Avoid drinking too many caffeinated beverages 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 at lunch.

2. Follow all of the above recommendations. There is no one-size-fits-all way to provide the body with the amount of vitamin D it needs. Studies show that supplements are a less effective source of nutrients than natural products, however, the diet is not able to provide the body with sufficient amounts of vitamin D. At the same time, the only reliable source vitamin D - sunlight - very dangerous in large quantities and can cause skin cancer. The best approach is to combine all three: nutritional supplements, exposure to sunlight, and proper diet.

   Be aware of the dangers of vitamin D deficiency. Every effort should be made to increase the level of vitamin D in the body, since its deficiency contributes to the development of a wide variety of chronic diseases. It was shown that low level vitamin D can lead to the development diabetes first type, chronic pain in muscles and bones, and various kinds cancer, including cancer of the breast, rectum, prostate, ovary, esophagus, lymphatic system.

   Find out if you are getting enough vitamin D. While 40-75% of people don't get enough vitamin D, some people are especially prone to vitamin D deficiency. You should be aware of the risk factors so that you can take appropriate measures, if necessary, that will help increase the level of vitamin D in the body. The risk groups include the following people:

   • people with Gunther's disease (chronic photosensitivity) - they do not tolerate sunlight;
   • those who rarely leave the house;
   • people with fear of sunlight;
   • those who, due to malnutrition, have an increased sensitivity to light;
   • infants who are exclusively breastfed;
   • patients with impaired absorption of fats;
   • those who constantly wear closed clothes;
   • older people whose skin perceives sunlight worse;
   • people who are in the room daytime, such as nurses and so on;
   • some people with strict dietary restrictions.

3. Get tested for vitamin D deficiency. A blood test for 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 get your vitamin D deficiency test results, you need to interpret them and make appropriate lifestyle changes. The test results are expressed in concentration units nmol/L (nanomoles per liter) (or ng/mL (nanograms per milliliter) in the US). This corresponds to the level of calcidiol in the blood, which is a reliable indicator of the level of vitamin D in the body.

• To be produced in the skin daily allowance vitamin D, it is enough to be in the sun for 30 minutes a day.
• Be careful when children, especially younger ones, are in the sun. Children should be exposed to the sun regularly, but additional safety measures should be taken, including the use of hats and long sleeves.
• Be in the sun in the late afternoon, when you can do without sunscreen. To get rid of the cream, you 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 are on the street mainly in dark time days, take a vitamin D3 supplement. Recommended daily dose is 4000-8000 IU (international units). Please check with your healthcare provider before taking any dietary supplement above 2000 IU.

Warnings

• If the sky is completely overcast, the UV energy is reduced by 50%; in the shade (or during 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 in this case, the part of the ultraviolet radiation that is transmitted by the clouds can burn the skin. Medium-wavelength ultraviolet radiation (UV B) does not pass through glass, so vitamin D is not produced by sunlight through a window.
• Vitamin D is fat soluble, so overdose is possible. This is true for all fat-soluble vitamins, which include vitamins A, D, E, and K. The maximum daily intake 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 is a softening of the bones in children, which can lead to fractures and curvature. Rickets can cause severe vomiting and diarrhea leading to rapid withdrawal from the body of vital trace elements.
  • AT possible consequences Vitamin D deficiency also includes dental problems, muscle weakness, often fractures of weak bones, curvature of the legs, deformity knee joints, curvature and deformation of the main bones in the skull, pelvis and spine, lack of calcium, which can lead to imperfect osteogenesis (disturbances in the process of bone formation).
  • Violation mental health such as depression or Alzheimer's disease.

Vitamin D (D), the so-called sun vitamin, what is so special about it? What role does it play in the human body and where can we get vitamin D?

As strange as it may seem now, there was a time when the ideal diet was considered: 12% protein, 5% minerals, 30% fat, and everything else is carbohydrates! Fortunately, now they no longer use such a diet, based only on meat and potatoes.

Today, everyone already knows that our body needs to receive many different nutrients. The ideal diet for our body or it is also called "cellular nutrition" is:

All this is necessary to maintain health in our body!

However, there is one interesting exception to this rule. Unlike other vital important vitamins, which we get from food, our body can also produce vitamin D itself with the help of sunlight.

So, let's look at how our body gets vitamin D and why it is so important for our health.

How is vitamin D formed in the body?

In fact, vitamin D is not just one vitamin, as we used to think. It's a lot of different chemical substances, which are collectively called "cholecalciferol". Cholecalciferol is inert in the body, which is why many are aware of the "inactive" form of vitamin D. Our body must convert this cholecalciferol into the active form of vitamin D, known as "calcitriol".

Basically, our body receives cholecalciferol (inactive vitamin D) from two different sources:

• sunlight
• and a small amount comes from food.

How do we get vitamin D from sunlight?

Our skin contains a substance called 7-dehydrocholesterol. When the skin is exposed to sunlight or ultraviolet light, this substance is converted into vitamin D3.

In other words, after vitamin D has entered the body, it is converted into the active form of calcitriol.

Why is vitamin D so important for our body?

From now on, I will talk about the activated form of vitamin D (D) - calcitriol. In fact, vitamin D is both a hormone and a fat-soluble vitamin, which is why it is so important for our body!

Vitamin D was originally noted as one of the important vitamins for maintaining skeletal health. For the first time, scientists have discovered that dogs that were raised indoors and deprived of sunlight were sick with rickets, a bone disease that was cured with vitamin D through sunlight and fish oil.

Vitamin D has since been proven to be involved in many processes in the body:

• Intestinal absorption

Vitamin D enhances the absorption of calcium from the intestines.

• Stabilizes calcium and phosphorus levels

The body requires a certain level of calcium and phosphorus in the blood. When levels drop, vitamin D helps our body maintain proper levels of calcium and phosphorus.

• Supports immunity

Vitamin D has several functions that support a healthy immune system.

• Affects our mood and brain development

Low vitamin D levels are associated with mood disorders and depression.

• Autoimmune disorders

Some studies have confirmed the relationship between multiple sclerosis and vitamin D deficiency.

• Bone health

Because vitamin D helps maintain blood calcium levels and increases the absorption of dietary calcium, which is essential for a strong skeleton!

• Cancer prevention

Some research suggests that vitamin D may help prevent certain forms of cancer.

About the benefits of vitamin D:

As you can see, vitamin D plays an important role in our body ...

How to saturate the body with vitamin D?

In general, we can get most of our vitamin D from sunlight, because. The body produces this hormone on its own. But most people work in indoors, where there is little direct sunlight, and in some countries there are long so-called seasons of darkness, when the sun appears for a maximum of two hours.

Luckily, there are other ways to get your vitamin D in!

Rickets was first described in 1650, at the end of the 18th century it became known that it was treated with fish liver oil. In 1924, scientists found that exposing children to ultraviolet light could prevent the disease. Thanks to this information in 1930-1932. scientists were able to get vitamin D.

Vitamin D - group biologically active substances(including ergocalciferol (D2) and cholecalciferol (D3)). The D vitamins are an essential part of the human diet.

Vitamin D is fat soluble. Vitamin D supports normal level and in the blood, both of which are needed for bone growth and strength.

Physico-chemical properties of vitamin D

Vitamin D is a colorless crystalline substance with a melting point of 120-121°C, insoluble in water (kalorizator). Let's well dissolve in all organic solvents: alcohol, fats, vegetable oils.

It is measured in International Units (IU). The daily dose for adults is 400 IU or 5-10 mcg, maximum allowable amount- 15 mcg. The dose of vitamin D for children is 400-500 IU.

After getting a tan, the production of vitamin D through the skin stops. People not exposed to the sun should take vitamin D supplements.

Vitamin D regulates metabolism in the body and is necessary for the hardening of newly formed bone tissue and, therefore, for the proper formation of teeth and bones, especially in childhood. It takes part in the process of cell growth and development. Is effective tool in the treatment and prevention of leukemia, cancer of the breast, ovaries, prostate, brain. Vitamin D coordinates the production of pancreatic insulin, i.e. affects blood glucose levels.

According to some information, by enhancing the process of assimilation and, vitamin D helps to restore the protective membranes surrounding the nerve, for this reason it is included in complex treatment multiple sclerosis.

Harmful properties of vitamin D

Vitamin D is harmful when it is overabundant. Daily doses of 25,000 IU over an extended period may cause toxic effects.

Manifestations of toxicity - unusual thirst, inflammation of the eyes, itching of the skin, vomiting, diarrhea, sudden urge to urinate, abnormal deposits in the walls of blood vessels, liver, lungs, kidneys and stomach.

Vitamin D deficiency can lead to rickets, tooth decay, stunted growth, lack of energy, muscle weakness, softening of the bones with subsequent deformation, and thinning of the bones, usually in old age. With a lack of vitamin D, a severe disease can develop - Crohn's disease, characterized by intestinal lesions. varying degrees. The intestine becomes inflamed in all departments, multiple ulcers occur, and complications can be irreversible: cracks, narrowing, bleeding, abscesses.

Too much vitamin D

Increased intake of the vitamin can cause intoxication of the body, while there is an increase blood pressure, decreased appetite, nausea, vomiting, kidney dysfunction, diarrhea, joint pain. So you should not allow an overdose of vitamin D, as well as its deficiency.

Vitamin D absorption

Vitamin D is present in many forms food products, the body can also produce it in the skin when you are in the sun. The ultraviolet rays act on the oils of the skin, promoting the formation of this vitamin, which is then absorbed into the body (calorizator).

When taken orally, vitamin D is absorbed from fat through the walls of the stomach.

For the best absorption of the vitamin, it is necessary to include foods rich in vitamins in your diet.