I've just recently started taking biotin consistently and my nails have been growing like crazy. It feels stronger and breaks less too. I haven't taken it long enough to comment on hair growth but I've heard it helps. However, just warning you guys that some people have had breakouts from this... But I haven't at all. Maybe it's because I take it with the b-complex, which I heard helps, but sometimes I take it by itself and I still haven't broken out. If you do get pimples, try to drink lots of water, take it with a b-complex, or take a lower dose.