Vitamin D: Why is it so important

Vitamin D: Why is it so important? We reveal the secrets of the “sun” vitamin

Part 1: Basics of vitamin D and its varieties

Vitamin D is not just one vitamin, but a group of fat -soluble runners playing a critical role in maintaining bones, immune system and general well -being. Unlike many other vitamins, vitamin D is produced in the skin under the influence of sunlight, which makes it unique and emphasizes the importance of staying in the sun (within reasonable limits, of course). However, given the geographical position, lifestyle and dietary habits, many people are deforming this vital nutrient.

There are two main forms of vitamin D, significant for humans:

• Vitamin D2 (ergocalciferol): This form of vitamin D is produced by plants and mushrooms under the influence of ultraviolet radiation. It can be found in enriched products, such as milk, juices and cereals, as well as in some mushrooms grown under the UV. Ergocalciferol is a form often used to enrich food.

• Vitamin D3 (cholecalciferol): This is a form of vitamin D, which is produced in human skin when exposed to sunlight (specifically, UVB rays). It is also found in animal products, such as fatty fish (salmon, tuna, mackerel), egg yolk and liver. Many studies show that vitamin D3 is more effective in increasing and maintaining the level of vitamin D in the blood compared to vitamin D2. This is due to the fact that vitamin D3 is better binded to the vehicle DTAMIN DTARINTER in the blood and is more effectively converted into an active form of vitamin D in the body.

The process of synthesis and activation of vitamin D:

The synthesis and activation of vitamin D is a complex process that includes several stages:

1. Synthesis in the skin (only for D3): Under the influence of UVB-rays of sunlight, 7-dehydrocholesterol, present in the skin, turns into previtamin D3.

2. Transformation into vitamin D3: Previtamin D3 is then isolated into vitamin D3 (cholecalciferol).

3. Transportation to the liver: Vitamin D3, produced in the skin or obtained from food, is transported to the liver.

4. Hydroxylation in the liver: In the liver, vitamin D3 is hydroxylating (adding a hydroxyl group-OH) under the influence of a 25-hydroxylase enzyme, turning into 25-hydroxyvitamin d [25(OH)D]also known as calciol. This is the main form of vitamin D, circulating in the blood, and its level is used to determine the status of vitamin D in the body. 25 (OH) D is the predecessor of the active form of vitamin D.

5. Transportation to the kidneys: 25 (OH) D is transported to the kidneys.

6. Gydroxylating in the kidneys: In the kidneys 25 (OH) D is subjected to further hydroxylating under the influence of an enzyme 1-alpha-hydroxylase, turning into 1.25-dihydroxyvitaminitamin D [1,25(OH)2D]also known as calcitriol. This is a biologically active form of vitamin D.

7. Calcitriol action: Calcitriol interacts with vitamin D (VDR) receptors in various body tissues, having its many effects.

Factors affecting the synthesis of vitamin D in the skin:

The effectiveness of the synthesis of vitamin D in the skin depends on many factors:

• Time of day and year: The synthesis of vitamin D is most effective in the middle of the day when the sun is at a zenith. In the winter months, especially in the northern latitudes, the angle of fall of sunlight is too small to ensure sufficient synthesis of vitamin D.

• Geographical latitude: People living further from the equator receive less UVB rays and, therefore, have a higher risk of vitamin D.

• Skin color: Melanin, the pigment responsible for skin color, absorbs UVB rays. People with dark skin need more time in the sun to synthesize the same amount of vitamin D as people with light skin.

• Age: With age, the ability of the skin to synthesize vitamin D decreases.

• Use of sunscreen: The sunscreen blocks UVB ray and, therefore, reduces the synthesis of vitamin D. However, it is important to remember that the sun protection is necessary to prevent skin cancer. It is recommended to observe the balance between the protection from the Sun and the sufficient stay in the sun for the synthesis of vitamin D. For example, you can spend a short time in the sun without sunscreen (usually 10-15 minutes for people with light skin) until the sunscreens are applied.

• Cloud and air pollution: Clouds and air pollution absorb UVB rays, reducing their amount that reaches the skin.

• Cloth: Clothing also blocks UVB rays. For the synthesis of vitamin D, it is necessary that the skin is open for sunlight.

Dietary sources of vitamin D:

Although the Sun is the main source of vitamin D, some foods can also contribute to its consumption:

• Fat fish: Salmon, tuna, mackerel and herring are excellent sources of vitamin D. The content of vitamin D varies depending on the type of fish and its origin (wild or grown).

• Egg yolk: Egg yolk contains vitamin D, but in smaller quantities than oily fish. The amount of vitamin D in egg yolk depends on the diet of chickens.

• Beef liver: Beef liver contains vitamin D, as well as other important nutrients.

• Enriched products: Many products, such as milk, juices, cereals and yogurts, are enriched with vitamin D. Enrichment of food products is an important way to increase vitamin D consumption among the population.

• Mushrooms grown under the UV light: Some mushrooms grown under ultraviolet light contain vitamin D2. It is important to note that ordinary mushrooms grown in the dark do not contain a significant amount of vitamin D.

Part 2: The role of vitamin D in health

Vitamin D plays many important roles in the body that go far beyond the health of the bones:

• Bone health: Vitamin D plays a key role in maintaining bone health, regulating the absorption of calcium and phosphorus in the intestine. It is necessary for the mineralization of bones and the prevention of rickets in children and osteomination and osteoporosis in adults. Vitamin D deficiency leads to a decrease in calcium absorption, which forces the body to mobilize calcium from bones, weakening them and increasing the risk of fractures.

• Immune system: Vitamin D plays an important role in the regulation of the immune system. It helps to maintain a balance between inflammatory and anti -inflammatory reactions, which is important for combating infections and preventing autoimmune diseases. Vitamin D (VDR) receptors are present on many immune cells, including macrophages, dendritic cells and T-lymphocytes, which allows vitamin D to directly affect their function. Studies show that vitamin D can reduce the risk of respiratory infections, such as flu and colds.

• Muscle function: Vitamin D is necessary to maintain muscle strength and function. Vitamin D deficiency can lead to muscle weakness, pain and increased risk of falls, especially in older people. Vitamin D affects the synthesis of protein in the muscles and improves their contractility.

• Cardiovascular system: Some studies associate vitamin D deficiency with a high risk of cardiovascular diseases, such as hypertension, coronary heart disease and heart failure. Vitamin D can have a protective effect on the cardiovascular system, regulating blood pressure, improving the function of the endothelium (internal lining of blood vessels) and reducing inflammation. However, additional studies are needed to confirm these effects.

• Mental health: Some studies show the relationship between vitamin D deficiency and an increased risk of depression, seasonal affective disorder (SAD) and other mental disorders. Vitamin D can affect the function of the brain, adjusting the production of neurotransmitters, such as serotonin and dopamine, which play a role in mood and cognitive functions. However, additional studies are needed to confirm these connections and determine the optimal dose of vitamin D to maintain mental health.

• Cancer prevention: Some studies suggest that vitamin D can play a role in the prevention of some types of cancer, such as colon cancer, breast cancer and prostate cancer. Vitamin D can affect the growth and spread of cancer cells, stimulating apoptosis (programmed cell death), suppressing angiogenesis (the formation of new blood vessels that feed the tumor) and modulating the immune response. However, additional studies are needed to confirm these effects and determine the optimal dose of vitamin D for cancer prevention.

• Metabolism of glucose and insulin: Vitamin D can play a role in the regulation of glucose and insulin metabolism. Some studies associate the deficiency of vitamin D with an increased risk of developing type 2 diabetes. Vitamin D can improve insulin sensitivity and contribute to the normal secretion of insulin with pancreas beta cells. However, additional studies are needed to confirm these effects and determine the optimal dose of vitamin D for the prevention and treatment of type 2 diabetes.

Part 3: Vitamin D: causes, symptoms and diagnosis

Vitamin D deficiency is a common problem around the world. According to estimates, about a billion people in the world have an insufficient level of vitamin D. This is associated with various factors, including insufficient sun stay, dietary restrictions, lifestyle features and some diseases.

Causes of vitamin D deficiency:

• Insufficient stay in the sun: This is the most common reason for the deficiency of vitamin D. People who spend most of the time in the room, wear closed clothes or live in regions with limited sunlight, are increased by increased risk of vitamin D.

• Dark skin: People with dark skin need more time in the sun to synthesize the same amount of vitamin D as people with light skin.

• Dietary restrictions: People who do not use products rich in vitamin D, or have dietary restrictions, such as vegans and vegetarians, are at increased risk of vitamin D.

• Obesity: Vitamin D is a fat -soluble vitamin, and in people with obesity more vitamin D stored in adipose tissue, which makes it less accessible to use by the body.

• Diseases: Some diseases, such as kidney diseases, liver diseases, cystic fibrosis and Crohn’s disease, can affect absorption, metabolism or the use of vitamin D.

• Age: With age, the ability of the skin to synthesize vitamin D is reduced, and the kidneys become less effective in converting vitamin D into its active form.

• Some drugs: Some drugs, such as glucocorticoids, antifungal drugs and anticonvulsants, can affect vitamin D.’s metabolism.

Symptoms of vitamin D:

Symptoms of vitamin D deficiency can be non -specific and often go unnoticed for a long time. In some cases, vitamin D deficiency can occur asymptomatic. However, a pronounced deficiency of vitamin D can lead to the following symptoms:

• Fatigue and weakness: This is one of the most common symptoms of vitamin D.

• Bone pain and muscles: Vitamin D deficiency can cause bone pain, especially in the lower back, pelvis and legs. It can also lead to muscle weakness and pain.

• Frequent infections: Vitamin D plays an important role in maintaining the immune system, and its deficiency can lead to increased susceptibility to infections.

• Slow wound healing: Vitamin D is involved in the healing process of wounds, and its deficiency can slow down this process.

• Hair loss: Vitamin D deficiency can lead to hair loss.

• Mood swings and depression: Some studies associate the deficiency of vitamin D with mood swings and depression.

• Rachite (in children): Rickets are a disease caused by vitamin D deficiency in children, which is characterized by softening and bone deformation.

• Osteomulation (in adults): Osteomlation is a disease caused by vitamin D deficiency in adults, which is characterized by softening of bones and an increased risk of fractures.

Diagnosis of vitamin D:

To diagnose vitamin D deficiency, it is necessary to take a blood test to determine the level of 25-hydroxyvitamin D [25(OH)D]. Level 25 (OH) D reflects vitamin D reserves in the body and is used to assess the status of vitamin D.

Recommendations on the interpretation of level 25 (OH) D:

• Deficiency: Level 25 (OH) D less than 20 ng/ml (50 nmol/l).

• Failure: Level 25 (OH) D from 20 to 29 ng/ml (50-75 nmol/l).

• Sufficient level: Level 25 (OH) D from 30 to 100 ng/ml (75-250 nmol/l).

• Toxicity: Level 25 (OH) D is more than 100 ng/ml (250 nmol/l). The toxicity of vitamin D is rare, but can lead to hypercalcemia (an increased level of calcium in the blood) and other health problems.

The doctor may prescribe additional tests, such as a blood test for calcium, phosphorus and parathyroid hormone (PTH), to assess the state of bones and exclude other diseases.

Part 4: Methods of maintaining the optimal level of vitamin D

Maintaining the optimal level of vitamin D is crucial for health and well -being. There are several ways to increase the level of vitamin D:

• Sun stay: Regular stay in the sun is the best way to increase the level of vitamin D. It is recommended to spend 10-15 minutes in the sun in the middle of the day, several times a week, without sunscreen (for people with light skin). People with dark skin need more time in the sun. It is important to remember the protection from the sun and avoid sunburn. It is necessary to observe the balance between obtaining a sufficient amount of vitamin D and protection against skin cancer.

• Diet: The use of products rich in vitamin D, such as oily fish, egg yolk, beef liver and enriched products, can help increase vitamin D.

• Vitamin D supplements: Reception of vitamin D additives is an effective way to increase the level of vitamin D, especially in the winter months or for people with vitamin D deficiency. The recommended dose of vitamin D depends on the age, health status and level of vitamin D in the blood. It is important to consult a doctor or nutritionist to determine the optimal dose of vitamin D for you. It is usually recommended to take vitamin D3, as it is more effective in increasing the level of vitamin D in the blood.

Recommendations for the dosage of vitamin D:

Recommendations for the dosage of vitamin D differ depending on age and health. General recommendations:

• Infants (0-12 months): 400 IU (international units) per day.

• Children (1-18 years old): 600 me per day.

• Adults (19-70 years old): 600 me per day.

• Adults over 70 years old: 800 me per day.

• Pregnant and lactating women: 600 me per day.

People with vitamin D deficiency may require a higher dose of vitamin D to achieve the optimal level. The doctor may prescribe a dose from 1000 to 5000 IU per day or even a higher dose for a certain period of time, and then reduce to a maintenance dose.

Cautions when taking vitamin D additives:

Taking vitamin D additives is usually safe, but it is important to observe certain precautions:

• Consult a doctor: Before you start taking vitamin D additives, consult a doctor, especially if you have any diseases or take other drugs.

• Follow the recommended dose: Do not exceed the recommended dose of vitamin D, if this is not recommended by a doctor. Excessive use of vitamin D can lead to toxicity.

• Control the level of vitamin D in the blood: Regularly control the level of vitamin D in the blood to make sure that it is within normal limits.

• Consider other sources of vitamin D: Consider vitamin D, which you get from food and sunlight, when determining the dose of vitamin D.

• Interaction with drugs: Vitamin D can interact with some drugs such as digoxin, thiazide diuretics and antacids containing aluminum or magnesium. Consult a doctor to learn about possible interactions with medicines.

Part 5: Vitamin D and modern research

Studies of vitamin D continue and expand, identifying more and more aspects of its effect on health. Modern research focuses in the following areas:

• Vitamin D and Covid-19: Many studies study the relationship between the level of vitamin D and the risk of infection Covid-19, the severity of the course of the disease and mortality. Some studies show that people with vitamin D deficiency are more often infected with COVID-19 and have a more severe course of the disease. However, additional studies are needed to confirm these results and determine the role of vitamin D in the prevention and treatment of COVID-19.

• Vitamin D and autoimmune diseases: Studies study the effect of vitamin D on autoimmune diseases, such as multiple sclerosis, rheumatoid arthritis and systemic lupus erythematosus. Some studies show that vitamin D can play a role in regulating the immune system and reducing the risk of developing autoimmune diseases.

• Vitamin D and brain health: Studies study the effect of vitamin D on cognitive functions and the risk of developing neurodegenerative diseases, such as Alzheimer’s disease and Parkinson’s disease. Some studies show that vitamin D can play a role in protecting the brain from damage and improving cognitive functions.

• Vitamin D and reproductive health: Studies study the effect of vitamin D on the reproductive health of men and women, including the fertility, pregnancy and health of newborns. Some studies show that vitamin D can play a role in the regulation of hormonal balance and improve reproductive function.

• Individualization of the dosage of vitamin D: Studies are aimed at developing personalized recommendations for the dosage of vitamin D, taking into account individual characteristics, such as age, skin color, health status and genetic factors.

Modern studies emphasize the importance of vitamin D for health and open up new opportunities for using vitamin D in the prevention and treatment of various diseases. It is important to monitor new studies and consult a doctor in order to get relevant information and recommendations for maintaining the optimal level of vitamin D.

Part 6: myths and errors about vitamin D

Around Vitamin D there are many myths and errors that can mislead and prevent the adoption of the right health decisions. We debunk some of the most common myths:

• Myth: Vitamin D deficiency is a rarity. Reality: Vitamin D deficiency is a common problem around the world, affecting about a billion people.

• Myth: If I live in the sunny region, I have no risk of vitamin D. Reality: Even in solar regions, people can experience vitamin D due to factors, such as the use of sunscreen, room stay, dark skin and age.

• Myth: Vitamin D intake in large doses is safe. Reality: excessive use of vitamin D can lead to toxicity, hypercalcemia and other health problems. It is important to observe the recommended dose and consult a doctor.

• Myth: Vitamin D can only be obtained from sunlight. Reality: Vitamin D can be obtained from sunlight, food and additives.

• Myth: Vitamin D is necessary only for bone health. Reality: Vitamin D plays an important role not only in bone health, but also in the immune system, muscle function, cardiovascular system, mental health and prevention of certain types of cancer.

• Myth: All vitamin D additives are the same. Reality: there are different forms of vitamin D (D2 and D3), and vitamin D3, as a rule, is more effective in increasing the level of vitamin D in the blood. It is also important to choose high -quality additives from reliable manufacturers.

• Myth: If I feel good, I have no vitamin D. Reality: Symptoms of vitamin D deficiency can be non -specific and often go unnoticed. For accurate diagnosis, it is necessary to take a blood test.

The debunking of these myths will help people make more reasonable health decisions and maintain the optimal level of vitamin D.

Part 7: The future of vitamin D research

Studies of vitamin D continue and develop, opening new horizons in understanding its role in health and diseases. In the future, studies will probably be focused on the following directions:

• Development of more accurate methods for assessing the status of vitamin D: Modern methods for assessing the status of vitamin D (blood test for level 25 (OH) D) have certain restrictions. In the future, more accurate methods can be developed that take into account the individual characteristics and metabolism of vitamin D.

• The study of genetic factors affecting vitamin D metabolism: Genetic factors play a role in vitamin D metabolism. The study of these genetic factors will develop personalized recommendations for the dosage of vitamin D.

• Development of new forms of vitamin D with improved bioavailability: Some people have difficulties in absorption of vitamin D from additives. The development of new forms of vitamin D with improved bioavailability will increase the effectiveness of additives.

• Studying the interaction of vitamin D with other nutrients: Vitamin D interacts with other nutrients, such as calcium, magnesium and vitamin K2. The study of these interactions will optimize dietary recommendations and improve treatment results.

• Conducting large -scale clinical studies to confirm the effectiveness of vitamin D in the prevention and treatment of various diseases: Large clinical studies are needed to confirm the effectiveness of vitamin D in the prevention and treatment of various diseases, such as COVID-19, autoimmune diseases and cancer.

Future studies of vitamin D promise to expand our knowledge about its role in health and diseases and lead to the development of more effective methods of prevention and treatment.