Does Biotin Make Hair and Nails Grow Faster?

Dr. Jo Herzog addresses the following question submitted by a Family Savvy reader.

Dear Dr. Herzog, my hairstylist told me to take biotin to make my hair grow faster and become longer and stronger. Is this true? If so, how much do I take?

Jo Herzog, M.D.

Biotin is a B vitamin. Your body does not make this by itself.  This vitamin is thought by some to help with the growth of hair and nails. I have found no sound scientific evidence of this but have taken a poll of several dermatologists. Some say they think it is nonsense, some say they think it helps, and one says that his wife is certain that it has helped her hair and nails.

So, what do we do when we encounter mixed results? We ask ourselves what this will cost and whether there is any harm to it. I think that this is harmless at reasonable doses, and it is also cheap; therefore, I take it myself. I take 3,000 mcg, but 3-5,000 mcg is probably a reasonable dose to take. A bottle at Costco (OTC but behind the pharmacy counter) costs a little over three dollars.