How much biotin should you take for hair growth? 2-5 milligrams
How long does it take biotin to work on hair? It takes months to see results on biotin. According to The Journal of Clinical and Aesthetic Dermatology (source), biotin takes around 90 days to begin to work. Contrary to some of the claims you may have heard, biotin is not an overnight remedy that will magically give you 5 inches of hair growth in 24 hours.
Does biotin thicken hair? Strengthens and thickens: Biotin “is well known for its positive effects on hair including growing stronger thicker strands,” says Friese. Protects: Because biotin strengthens hair, it is less likely to break off at the ends, promoting and protecting length, explains Friese.