Vitamin H (biotin, vitamin B7)- a white crystalline substance, destroyed at high temperature and soluble in an alkaline aqueous medium. Biotin is involved in the formation of fatty acids and some biologically active substances.
Biotin is able to be produced by the intestinal microflora, but this is not enough to meet the body's need for vitamin H.
On average, the daily intake of biotin is 30-100 mcg. The daily requirement for biotin in pregnant and lactating women is increased by 20 micrograms.
Functions of vitamin H in the human body
- Biotin regulates blood sugar levels and is very important for carbohydrate metabolism. Vitamin H controls the processes of gluconeogenesis, being responsible for the participation of glucose in metabolism.
- Biotin plays an important role in protein digestion and fat burning.
- Vitamin B7 contains sulfur, which is very important for the health of hair, nails and skin - biotin is also called the "beauty vitamin".
- Vitamin H is necessary for the normal functioning of the nervous system.
- Biotin is involved in the synthesis of beneficial intestinal flora.
Symptoms of deficiency and excess of vitamin H
In the body, with a lack of biotin, the level of sugar and cholesterol in the blood rises, anemia develops, weakness, drowsiness, muscle pain, loss of appetite, depression, and nausea occur. Obvious signs of vitamin H deficiency will be hair loss, dandruff, excessively oily or excessively dry skin.
With hypervitaminosis of biotin in the human body, side effects are not observed. Even a prolonged overdose of vitamin H does not cause any pathologies.
The content of vitamin H in food
Interestingly, biotin is found in varying amounts in almost all foods. However, the maximum content of vitamin H is in nuts, boiled eggs, soybeans, liver and kidneys of large domestic animals, yeast, and milk. Spinach, cabbage, red beets are rich in vitamin H from vegetables. Biotin is also found in champignons and porcini mushrooms, strawberry and blueberry leaves, and fruits.
Applications and Interactions of Vitamin H
Fans of raw egg white should be aware that it contains the anti-substance biotin (avidin), which interferes with the absorption of vitamin H. In such cases, it is recommended to increase the daily intake of biotin and not to consume raw eggs and vitamin H at the same time.
Antibiotics and alcohol interfere with the synthesis and absorption of biotin.
To increase the activity of vitamin H, it is useful to take it together with magnesium.
Vitamin H is a useful water-soluble substance that is involved in many biological processes and the synthesis of vital elements. This substance is also known as biotin, vitamin B 7 and coenzyme P.
A bit of history
The prerequisites for the discovery and study of biotin appeared as early as 1916. Bateman then discovered that laboratory rats fed raw egg white suffered from neuromuscular disorders, alopecia, and dermatitis. And in animals whose diet included boiled protein, such symptoms were not observed.
In 1936, scientists Kegl and Tennis isolated a factor from chicken eggs that stimulates the growth of yeast fungi. The crystalline substance was called biotin. In the course of subsequent studies, it turned out that it is he who protects the body of laboratory animals from the harmful effects of raw egg white.
In 1942, Du Vignot derived the formula of biotin, and after some time it was synthesized in the laboratory. At the same time, research began on the antagonist substance biotin, which is contained in the egg white.
In 1940, the antagonist was isolated by the scientist Akin. The substance was named "avidin". As it turned out, it binds biotin and makes it difficult for the body to absorb it.
Functions of Vitamin H
Each nutrient plays its own unique role in the body. For example, biotin performs the following functions:
- takes part in the process of cell division, growth and regeneration;
- contributes to the normal absorption of B vitamins;
- ensures the normal metabolism of proteins and fats;
- eliminates muscle pain and fatigue;
- fights dermatological problems;
- prevents hair loss;
- contributes to the formation of healthy intestinal microflora;
- strengthens the immune system;
- improves the state of the nervous system;
- takes part in the production of collagen;
- slows down the aging process of the body;
- normalizes the process of processing glucose.
How does biotin deficiency manifest?
Vitamin H is vital for the normal functioning of the body. If the substance is not enough, you will immediately feel it. The symptoms of biotin deficiency are as follows:
- dryness, peeling, irritation and other skin problems of the extremities;
- unhealthy complexion (pallor, earthiness);
- pale smooth surface of the tongue;
- constant sleepiness;
- emotional depression and depression;
- pain and feeling of weakness in the muscles;
- elevated levels of "bad" cholesterol in the blood;
- increased blood sugar;
- anemia;
- lack of appetite;
- deformation and fragility of the nail plate;
- irritability;
- headache attacks;
- frequent bouts of nausea;
- violations in the work of the sebaceous glands;
- a sharp deterioration in the functional state of the hair and a slowdown in their growth.
Biotin Deficiency Factors
Vitamin H deficiency in the body can develop for several reasons. Here are the main ones:
- genetic diseases associated with a violation of the absorption of biotin (there are approximately 5 cases per 100,000 people);
- taking antibiotics and sulfonamides, which destroy the intestinal microflora (where biotin is usually synthesized);
- long-term restriction in nutrition (for example, strict diets);
- indigestion associated with asthenia of the mucous membrane of the stomach and intestines;
- the use of saccharin, which adversely affects the metabolism of the vitamin;
- regular consumption of raw eggs (their protein contains avidin, which interacts with biotin);
- the use of products that contain preservatives E221-228 (sulfur compounds that destroy biotin when heated or in contact with air);
- frequent use of alcoholic beverages (alcohol interferes with the absorption of biotin).
Main indications
The intake of biotin in the form of a dietary supplement or a medical preparation should be agreed with the doctor. As a rule, specialists prescribe such funds in such cases:
- biotin deficiency in newborns (manifested as violations of the intestinal microflora, hair loss or deterioration of the skin);
- low blood sugar;
- disorders of the nervous system;
- fragility and delamination of nails;
- fragility and hair loss;
- muscle weakness;
- apathy and decreased performance;
- long-term use of antibiotics and drugs for seizures;
- inadequate diet.
Excess Biotin
If there is too much vitamin H (biotin) in the body, this is also not very good. This situation can occur with the wrong diet or with uncontrolled intake of drugs. Excess biotin in the body can be identified by the following signs:
- excessive sweating;
- skin rashes;
- exacerbation of infectious and chronic diseases;
- problems with insulin production;
- increased glucose levels;
- frequent urination.
Possible negative consequences
Most domestic experts agree that biotin is safe and non-toxic in doses up to 300 mg per day (with intravenous administration - up to 20 mg per day). Given the fact that the vitamin is water soluble, excess is excreted from the body naturally along with urine.
However, American experts have a different opinion. The danger of biotin is that its excess can cause distortion of laboratory tests. For example, when testing blood for thyroid hormones, a picture similar to Graves' disease can form. The result of a heart attack biomarker may also be underestimated. Thus, the wrong treatment may be prescribed.
You need to be especially careful with dietary supplements designed to improve the condition of hair, nails and skin. They can contain up to 600% of the daily intake of vitamin H. Such huge doses can only be prescribed by a doctor in exceptional cases. If you, nevertheless, take biotin, be sure to warn the laboratory assistant about this when taking blood for analysis (especially when it comes to heart problems).
Elixir for hair
Vitamin H is the basis for healthy and beautiful hair. It has such a beneficial effect on the hair:
- biotin normalizes the concentration of red blood cells, which, in turn, provide oxygen transport, which is vital for the normal functioning of hair follicles;
- biotin stimulates insulin metabolism, which, in turn, ensures the supply of glucose to the surface of the scalp;
- Biotin regulates the production of keratin, which is one of the main "building materials" for hair.
To maintain the normal condition of the hair and prevent hair loss, it is recommended to use vitamin H in ampoules (add the contents to a portion of the shampoo before each wash). For the treatment of alopecia, it is necessary to take a vitamin inside.
Daily requirement for vitamin H
Reception of any vitamins should not be uncontrolled. For each useful substance there is the concept of a daily norm, which ensures the saturation of the body, but does not lead to an overdose. For vitamin H (biotin), the following indicators are true:
- For preventive purposes (to prevent muscle weakness and hair loss), you need to consume 5 mg of biotin per day.
- In order to dull pain during intense physical exertion, as well as to build muscle mass, it is recommended to take 1 mg of biotin per day.
- To compensate for the lack of vitamin H (identified by the results of a medical examination), as well as for the treatment of baldness, as a rule, 10-15 mg of the substance is prescribed per day.
Interaction with other drugs
When taking biotin, there are some restrictions on combining it with other drugs. The first thing to note is that vitamin H interacts well with all B vitamins. But the best results are observed when taking biotin with vitamins B5, B9 and B12.
It makes no sense to take biotin at the same time as antibiotics, because due to the destroyed intestinal microflora, the vitamin will not be able to be absorbed in the body. For the same reason, you should not use it at the same time as sulfur-containing drugs and sugar substitutes. Also, the absorption of the beneficial substance is negatively affected by almost all anti-cold drugs.
Where to look for biotin
Ideally, a person should receive all vital substances with food. To do this, it is extremely important to form the right balanced diet. Here are some foods that contain vitamin H:
- nuts;
- cod;
- egg yolk (boiled);
- legumes;
- cottage cheese;
- oats;
- hard cheeses;
- wheat;
- rice bran;
- sea fish;
- spinach;
- cauliflower;
- offal;
- yeast;
- milk;
- White cabbage;
- beet;
- White mushrooms;
- Champignon;
- blueberry and strawberry leaves;
- salmon;
- pork;
- raspberries;
- avocado;
- sunflower seeds;
- bananas.
How to "save" biotin
There are many sources of vitamin H in food. The fact is that during heat treatment, canning and soaking in water, marinades and other solutions, biotin in products begins to decompose. If you want to get the most out of your food, keep these tips in mind:
- try to consume food fresh (if possible) or minimize processing;
- boil vegetables in a peel and under a lid;
- the best cooking method is baking in foil or a sleeve;
- before sending food for storage in the refrigerator, do not wash or grind them;
- do not expose products to long-term storage (even on the top shelf of the refrigerator) for more than three days;
- the best way to harvest vegetables and fruits for the winter is freezing.
Vitamin B7 - aka biotin - is extremely important for the nervous system, skin, hair, nails, liver, and for the normal development of the fetus.
“This vitamin is a stranger among his own,” explains gastroenterologist, candidate of medical sciences Konstantin Spakhov. - Why? It is often said that there is practically no deficiency of it: there is a lack of other vitamins, but vitamin B7 is not. Meanwhile, deficiency is the most important property of vitamins as such. Usually, almost mythical stories are cited as examples of biotin deficiency about some weirdos who supposedly could not live without a dozen raw eggs a day, and so they developed this condition. Such tales wander from one medical book to another. They explain it this way: there is a lot of this vitamin in the egg yolk, but the protein contains the substance avidin, which blocks the absorption of biotin, and its severe deficiency develops. Such a mechanism does exist: crude protein avidin will block the absorption of biotin, and in a boiled or fried egg, avidin itself is denatured and becomes safe for vitamin B7. But how often does this happen in reality? It's hard to believe that there are freaks who are obsessed with raw eggs in such huge quantities.
In fact, it is difficult for a healthy person to be deficient in vitamin B7. First, you need very little, only 50 micrograms per day (1 microgram is just one millionth of a gram). For this, biotin is called a microvitamin. Since it is found in many foods, this meager dose is easy to get. Secondly, biotin is also produced by bacteria in our intestines. And this is another way to protect us from its deficiency. And then all sorts of “buts” begin.
For example, if a person has a problem with the intestinal microflora: dysbacteriosis or conditions after a long course of antibiotic treatment. And in such cases, vitamin B7 deficiency becomes a reality: bacteria produce very little of it. Another example: excessive addiction to alcohol. It also interferes with the absorption of biotin, as does raw egg white.
Pregnant and lactating mothers are at risk. They have a higher need for biotin, and its deficiency can develop even with normal consumption. And if a woman has toxicosis and she cannot eat the required amount of food, then the risk of deficiency is very high. According to some reports, about a third of all pregnant women are significantly deficient in this vitamin. In people with Crohn's disease, it, along with other lesions of the large intestine, can also cause a severe lack of biotin.
There is another reason for the shortage, the most serious one. Defect of the enzyme biotinidase, necessary for the absorption of vitamin B7. This is a congenital condition that can be corrected by increased intake of biotin in the form of drugs. The problem is that this disease is not always detected.
What does biotin do in the body and how much is needed?
B7 is a coenzyme. This is the name of the substances that are part of the enzymes and help them to work actively. Vitamin B7 plays an important role in the metabolism of fats, proteins, carbohydrates and a number of other processes in the body. Therefore, the range of symptoms that occur with its deficiency is quite wide. And in order to avoid them, this atypical vitamin must still be treated carefully.
Table. Daily requirement for vitamin B7 depending on age (mcg)
What foods to look for biotin?
Vitamin B7 is found in the mass of products, albeit in small quantities. And, despite the fact that these doses, it would seem, are not very significant - up to 3-4% of the daily intake (DNR) - they actually play a significant role in preventing its deficiency. But there are foods that contain a lot of biotin (see table), do not forget to include them in your diet regularly.
Table. Biotin content per 100 grams of product
| Product | Biotin content (mcg) | Daily intake, % |
| Chicken liver | 170 | 340 |
| Chicken egg yolk | 56 | 112 |
| Beef and pork liver | 40 | 80 |
| Chicken egg, oatmeal (any), peas | 15-20 | 30-40 |
| Rice, barley and wheat porridge, chicken, cod | 10-12 | 20-25 |
| Meat (broiler chickens), cottage cheese of any fat content, salmon, corn porridge, soft cheese (such as camembert and brie) | 5,1-8,4 | 10-17% |
How to determine when vitamin B7 is not enough?
The first and most typical signs are hair loss, brittle nails, dry and flaky skin. They develop gradually and for a long time. Often there are dryness and redness of the skin around the openings of our body: mouth, nose, eyes. There may be atrophy of the taste buds on the tongue with loss of taste. General weakness, depression, drowsiness or insomnia - all this is also possible.
Children's share
A special situation with respect to biotin is a congenital deficiency of the enzyme biotinidase. It can be detected with the help of newborn screening, but we do not do it en masse. Testing is usually done randomly and usually on suspicious cases when a child has symptoms that could be related to the condition. As a rule, these are convulsions, hearing and vision loss and other signs of damage to the nervous system, as well as skin problems and hair loss or absence (alopecia), frequent infections. Among such children, enzyme deficiency was detected with a frequency of 1: 1000. That is, this disease is not so frequent, among all newborns it occurs in one child out of 20-40 thousand. When should you consider testing for biotinidase deficiency? Most often, this condition begins to manifest with convulsions that do not go away with the appointment of specific drugs. And with the addition of biotin, everything returns to normal. Vitamin B7 supplements should be taken for life.
Usually the diagnosis is made between the ages of 1 month and 6. But it is best done immediately after birth or in the first month of life. If biotin treatment is started at this age, mental retardation can be prevented. If later, then skin and hair problems will pass, but neurological changes may remain. By the way, the World Health Organization recommends including a biotinidase deficiency test in newborn screening.
Chemical formula of biotin: C 10 H 16 N 2 O 3 S.
Description
The first mention of the vitamin appeared in 1901, when scientists discovered it as a biologically active substance isolated from yeast. Then the same biologically active substance was isolated from the egg yolk.
Biotin is synthesized in significant amounts by the intestinal microflora. The intensity of this process depends on the species composition of carbohydrates in the diet.
Biotin Sources
Traditional food sources of biotin are liver, kidneys, legumes (soy, peas), eggs, yeast.
Biotin is widely distributed in nature and is found in both plant and animal products (see table).
| Vegetables, fruits, berries, grain products | Biotin content | Vegetables, fruits, berries, cereals | Biotin content |
| Peanut | 40 | Spinach | 7 |
| green beans | 7 | oranges | 2 |
| soy beans | 60 | Melon | 3 |
| Dry green peas | 35 | strawberries | 4 |
| Peas yellow dry | 18 | Peaches | 1.7 |
| Champignon mushrooms | 16 | Apples | 9 |
| White cabbage | 24 | Corn | 6 |
| Cauliflower | 17 | Wheat | 10 |
| Potato | 0,5-1 | Whole wheat flour | 9-25 |
| fresh onion | 3.5 | Whole wheat flour bread | 2-5 |
| dry onion | 28 | Wheat flour I grade | 1-2 |
| Carrot | 2.5 | Wheat flour of the highest grade | 1 |
| Salad | 3 | Rice | 12 |
| Beet | 2 | rice bran | 46 |
| tomatoes | 4 | Barley | 6 |
| Biotin content | Dairy, meat and fish products | Biotin content | |
| Women's milk | 0.1 | Pork | 2-75 |
| cow's milk | 5 | pork liver | 250 |
| Condensed milk | 15 | Veal | 15-2 |
| milk powder | 40 | Calf's liver | 100 |
| Low fat cheese | 4 | Salmon | 5-10 |
| whole chicken egg | 9 | Canned salmon | 10-20 |
| Chicken egg, yolk | 30 | sardines | 24 |
| Mutton | 2-2.7 | Herring | 4 |
| Beef | 5 | Halibut | 8 |
| Beef liver | 200 | Tuna | 4 |
| beef heart | 8-50 |
Daily requirement for biotin
Table. Norms of physiological need for vitamin H depending on age in Russia [MR 2.3.1.2432-08]
Tolerable Upper Intake Levels for Biotin for Adults is 150 mcg per day (“Unified sanitary-epidemiological and hygienic requirements for goods subject to sanitary-epidemiological supervision (control)” of the EurAsEC Customs Union).
Manifestations of biotin deficiency
The initial manifestations of biotin deficiency are expressed in flaking of the skin without itching. Then it is possible to develop scaly dermatitis of the neck, arms, legs, turning into pityriasis peeling of the skin with the addition of depression, fatigue, drowsiness, muscle pain, loss of appetite, and an increase in serum cholesterol levels.
In young children, biotin deficiency is manifested by skin disorders in the form of dermatitis with peeling on the neck, hands, forearms, legs, followed by gray pigmentation. Attached are lesions of the tongue, anorexia, nausea, muscle pain, anemia. With the use of biotin, improvement occurs.
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Interactions
Raw egg white contains a substance called avidin, the anti-vitamin biotin. This substance binds biotin and prevents its absorption into the blood. When heated, denaturation (irreversible structural damage) of avidin in the egg white occurs, and therefore cooked eggs do not interfere with the absorption of biotin.
These vitamin-mineral complexes contain this vitamin:
* dietary supplement. NOT A DRUG
The daily rate of Vitamin B7 (biotin) for healthy skin, hair and nails, as well as the interaction with other components and in which products it is contained.
It is known that for normal functioning the body needs a sufficient amount of vitamins and minerals. One of them is biotin or vitamin B7, which is involved in many life processes of the body.
What is biotin and why is it needed
Biotin is one of the 8 B vitamins. It performs a number of extremely important functions in the human body, some of which are unique to it. This water-soluble vitamin was discovered in 1901. It can be synthesized by the intestinal microflora, but for this it must be absolutely healthy.
The substance regulates the following processes:
- helps to improve the functioning of the digestive tract;
- reduces the level of "bad";
- participates in the production of fatty acids;
- heals nerve tissues and bone marrow;
- normalizes metabolic processes;
- maintains good condition of the tendons;
- essential for healthy skin, nails and;
- in combination with chromium, it restrains blood sugar levels in diabetics;
- ensures normal cell growth.
Release form of the drug
It is desirable that the body receives the necessary dose of vitamin B7 from natural products. If necessary, the lack of a substance is replenished with pharmaceutical preparations. It is available in tablets, capsules or ampoules for injection. The required dosage and rules for taking the drug are indicated in the instructions.
It can be taken as part of a multivitamin supplement if prescribed by a doctor. Well-established drugs such as "Biotin-complex"(daily dose - two tablets), "Wolvit"(take one tablet daily) "Biotin Forte Germany" And "Medobiotin".
Injections are prescribed for people with bowel disease. Intramuscular injections are given once a day. Sometimes the contents of the ampoule are rubbed into the skin. As a result, rashes and inflammation disappear. In each case, the form of release of the drug and the method of its application is chosen by the doctor.
What does vitamin B7 deficiency lead to?
Vitamin B7 deficiency is not often diagnosed, but such cases do occur. Its deficiency leads to the intake of certain antibiotics and antibacterial agents. Frequent alcohol consumption leads to the suppression of healthy intestinal microflora, which in turn reduces the production of this substance in the body.
The abuse of saccharin, products with additives E221 - 228 also leads to a lack of a vital component. Acute and chronic diseases of the gastrointestinal tract can be responsible for biotin deficiency.
It is impossible to identify a deficiency of B7 by passing tests. It is identified by characteristic symptoms and complaints. The consequences of biotin deficiency are manifested in the form of the following disorders:
Insufficient synthesis of fatty acids, as a result of which, first of all, the skin suffers. There are such unpleasant consequences as psoriasis, dermatitis, seborrhea. Conjunctivitis also appears, decreases.
- Metabolism is disturbed, which leads to loss of appetite, nausea, weakness, drowsiness and depression.
- In some cases, blood pressure drops.
- Observations of diabetics have shown that a lack of vitamin B7 increases the level of sugar in the patient's blood.
- The muscles of the arms and legs become weak.
If this problem is not identified and eliminated in a timely manner, dermatitis, diabetes, baldness, and depression will appear.
Daily requirement for women
This important component provides youth and health to the skin and hair, strengthens brittle and dull nails. The fair sex should take care of a sufficient amount in the body. It is known that when it is lacking, nails become brittle and dull, hair falls out, and the skin becomes inflamed and flaky. Many doctors believe that the appearance of early gray hair is also a consequence of B7 deficiency.
Cosmetics manufacturers have begun to add youth vitamin to skin and hair care products. However, it has been proven that it is not absorbed when applied externally, it must be taken orally.
For the normal course of all important processes, a woman needs 30-50 micrograms of biotin to enter the body.
What foods contain B7
Many food products contain this useful substance, from where it is easily absorbed. Biotin is found in brewer's yeast, beef liver and heart, eggs, raspberries, avocados, sunflower seeds.
Vegetables such as potatoes, onions, carrots, tomatoes, cabbage, spinach, beets and corn also have it in their composition. B7 is found in nuts, peaches, apples, oranges, bananas and melons.
Sources of biotin are meat, sea fish, cereals and legumes. It is found in small amounts in dairy products.
Compliance with the rules of a healthy diet will help maintain normal levels of vitamin B7. And eating natural yoghurts and other fermented milk products preserves a healthy microflora and provides an opportunity to synthesize biotin on your own.
age-related vitamin intake
The daily requirement of biotin depends on the age of the person. For infants 0 to 6 months old, 5 micrograms per day is sufficient. Children under one year old need 6 mcg per day. At the age of 1 to 3 years, children need B7 in the amount of 8 mcg.
For school-age children, the norm is 12 mcg, for adolescents - 20 mcg. Adults should receive 30 mcg per day. For pregnant and lactating women, this figure rises to 50 mcg and above.
Taking during pregnancy
During pregnancy, taking biotin is not only possible, but necessary. Recent studies have shown that expectant mothers in the body often lack it. It is necessary for the proper development of the child.
Researchers at the Institute of Medicine have found that biotin is as important during pregnancy as iron. It also prevents congenital anomalies in the fetus.
As a rule, the lack of this substance is more pronounced towards the end of the pregnancy. Women who are expecting the birth of a child are advised to make up for the lack of B7 by correcting nutrition. It is better not to drink dietary supplements in this position. They contain various auxiliary components that can cause an allergic reaction.
Overdose
An excess of biotin in the body is unlikely, as it is well absorbed, and the excess is naturally excreted. It does not accumulate in the body.
Very rarely, with the use of a large amount of vitamin observed or frequent urination.
The substance has no contraindications, except for individual intolerance. An allergic reaction to it is extremely rare.
Interaction with other components
Vitamin B7 goes well with other components from the B group - B12, B5 and B9. When used in the correct dosage, it interacts well with magnesium. It is synthesized by symbiotic bacteria in a healthy gut and is easily absorbed from foods.
However, the use of a number of substances destroys the structure of the vitamin or prevents its formation and absorption:
- The use of crude protein does not allow biotin to penetrate into the blood. The egg contains avidin, which is considered the antivitamin of biotin. After heat treatment, this component does not interfere with the absorption of B7.
- The use of alcoholic beverages reduces the body's ability to absorb this essential substance.
- The use of fats that have undergone prolonged heat treatment is also the reason for the slow absorption of biotin.
- This process is hampered by antibiotics and other medicines that contain sulfur.
- Taking a sugar substitute negatively affects the absorption of vitamin B7.
The intake of this component in the body is one of the conditions for a person to feel well. Together with other vitamins, it ensures the normal course of all vital processes. Knowing what foods contain it, you can easily control its sufficient intake.
Review
Elena 38 years old
I read that, according to scientists, in dietary supplements with biotin to strengthen nails and hair, there is often an increased content of this substance by several times. Before buying, consult your doctor and establish your daily requirement for this vitamin.
