The vitamin that promotes hair growth is biotin, also known as vitamin B7. Biotin stimulates the production of keratin, which is essential for hair growth, and it has functions in creating red blood cells that carry oxygen and nutrients to the scalp and hair follicles
. Other vitamins that are associated with supporting healthy hair growth include vitamin D, vitamin C, zinc, and iron
. Vitamin D deficiency has been linked to hair thinning and hair loss
