There is no scientific evidence that biotin helps hair grow, states WebMD. Such claims are unsupported or untested. Biotin supports metabolism and promotes health in the skin, nerves, digestive tract and cells.
The effects of biotin on the human body are being researched in an effort to confirm if it can be used to treat other conditions, such as nerve pathology and type 2 diabetes, or if it helps strengthen brittle nails, says WebMD. There has been promising research supporting the claim that biotin decreases insulin sensitivity in individuals with type 2 diabetes; however, a true biotin deficiency is very rare, reducing the need to supplement it. Biotin is readily available in numerous food sources, and the body recycles previously used biotin.