How long does it take for fish oil to work for hair?
How long does it take for fish oil to work for hair? After about six months, eight people (representing 80 percent of participants) had an increase in hair. It’s important to remember, though, that this was a very small study and there was no placebo group. An earlier study, with 120 participants, was published in 2015 in the Journal of Cosmetic Dermatology.