I can attest to the biotin pills working miracles. I've taken them for about two years now. Just a few things. Never take more than 5mg or 5000mcg a day. It's best to take a higher end brand of biotin. The lower priced biotin from let's say Walmart or target have low quality fillers which is what causes people to breakout. I use the GNC be beautiful which has 3mg or 3000mcg biotin and they made my nails grow thick and strong. The most beat part was the my hair grew but I also had an increase in sebum production. My eyelashes also grew long but that was after a year of use. I highly recommend this stuff