Niacin isn’t something you hear about everyday in passing so for the most part we tend to not focus on it as much. Niacin* is crucial to accelerating hair growth, which is also why you have to be VERY careful not to consume too much of this B-vitamin (unless you don’t mind increased growth all over).
This vitamin is water soluble, and is known to dilate your blood vessels, which can increase circulation to your scalp that directly correlates to longer hair.
This vitamin not only helps with circulation, but also helps with controlling cholesterol. When cholesterol builds up, it produces an enzyme that is linked with balding in both men and women so having niacin* in your diet is crucial.
Niacin is on the back of many supplement bottles, but you can get it from almost any meat (fish, chicken, turkey, pork), mushrooms, sunflower seeds, and avocados.