Biotin is a water-soluble B-complex vitamin that helps the body metabolize proteins and process glucose. It is also known as vitamin B7 or vitamin H.
The human body cannot synthesize biotin. Only bacteria, molds, yeasts, algae, and certain plants can make it, so the diet needs to supply it.
Unused biotin is eliminated in urine, so the body does not build up reserves. It must be consumed daily.
Biotin supplements are widely available in health food stores, but biotin deficiency is rare, and there is little evidence to suggest that most people need them.
What is biotin?
Biotin comes from a healthy diet.
Biotin is a coenzyme involved in the metabolism of:
Fatty acids, a type of molecule found in fats and oils
Leucine, an essential amino acid that humans cannot synthesize
Gluconeogenesis, the synthesis of glucose from molecules that are not carbohydrates, for example, amino and fatty acids
Coenzymes are substances that enhance an enzyme’s action. Coenzymes cannot trigger or speed up a biological reaction, but they help enzymes do so.
Why is it important?
The University of Maryland Medical Center (UMM) explain that biotin is important in helping the body to process glucose and to metabolize proteins, fats, and carbohydrates. It also helps to transfer carbon dioxide.
According to the European Food Safety Authority, biotin contributes to:
Metabolism of nutrients
Maintaining hair, skin and mucous membranes
Nervous system function
Biotin contributes to healthy nails, skin and hair, so it features in many cosmetic and health products for the skin and hair. However, it cannot be absorbed through hair or skin.
Nails and hair loss
Biotin is sometimes called vitamin H. The “H” comes from the German words for hair and skin, “Haar” und “Haut.”
Some small studies have suggested that taking a 2.5-milligram supplement of biotin for 6 months can increase fingernail strength and reduce the tendency of nails to split.
However, there is no evidence until now that biotin can prevent or treat hair loss in men or women.
A lack of biotin has been linked to cradle cap in infants, but there is no evidence that biotin supplements, for example, in formula milk, might help.
Biotin and diabetes
Since biotin aids metabolism, it could play a role in controlling diabetes. Research has suggested that B7 can improve the use of glucose in the body. People with diabetes have a problem using glucose, because of an insulin imbalance. Biotin appears to improve the synthesis of fatty acids, enhance the storage of glucose. In rats, it has been found to stimulate the secretion of insulin.
Some reports have suggested that biotin supplements can improve symptoms of neuropathy, for example, in people with diabetes. However, these have not been confirmed by research.
One study found that people with diabetes had lower levels of biotin than people without the condition.
In another, people who had lost their sense of taste reported improvements after taking an additional 10 to 20 micrograms a day of biotin.
However, research into the benefits of biotin has been too limited so far to draw any firm conclusions.