Does Biotin Make Your Hair or Nails Grow?
Q. I am trying to grow my hair and I am currently taking a supplement containing biotin that's supposed to good for your hair, skin, and nails. Does this nutrient really make your hair grow?
A. Biotin deficiency (which is pretty rare) can cause your hair to fall out but so far there's no solid evidence showing that taking extra biotin can prevent or treat hair loss or make your hair grow thicker or more quickly. Of course, that doesn't stop them from selling it as a "hair-strengthening" supplement.
There's actually a bit more evidence to support the idea that taking biotin supplements can help strengthen brittle nails. The studies have been small and not terribly rigorous. More research would have to be done to confirm the results. But if you suffer from weak, brittle nails, a biotin supplement might be worth a shot.