My answer to What are the best vitamins for thicker hair?
Answer by Nature Crazy:
1. Biotin (B7). Not only is it a key component in the hair manufacturing process but it is also essential to grow new hair. To top that off it plays an important role in health of skin and nails and scientific studies have even linked biotin deficiency to hair loss. (see study below) Supplementing with extra biotin can thicken hair and you might want to utilize a natural shampoo that contains biotin as well.
2. Niacinamide (vitamin B3) has a plethora of applications for fighting hair loss and thickening one’s hair. Besides its ability to reduce the negative influences of mast cells on fibrosis, Niacinamide inhibits vasoconstriction, allowing better blood flow and circulation. This is extremely beneficial for the hair and skin.
3. Vitamin A performs a unique role in a variety of factors regulating hair growth. For example, in its proper form it can reduce the effects of androgens on the sebaceous gland which is very beneficial for the hair. Hair growth treatments in the past have observed that adding retinol (vitamin A) to them gave a boost in hair.
Tip: Keep in mind, that vitamins, nutrients, and minerals almost never work in isolation and are interdependent on one another. In other words, they work in tandem. Getting adequate amounts of every vitamin (A, B, C, D, and E) is critical.