Biotin is a vitamin that is thought to promote hair growth, according to LaurenConrad.com. This vitamin is present in prenatal vitamins, which also include iron and folic acid. Vitamin D and sufficient daily intake of protein are also important to healthy hair growth, reports WebMD.
While vitamin D and biotin are found in supplements, WebMD indicates that a balanced diet is the key to healthy hair. Copper, calcium, vitamin E and the amino acid cysteine are also helpful in maintaining healthy hair.
Salmon, almonds, walnuts and peanuts contain many of the necessary nutrients for hair growth. Other helpful foods include oatmeal, fish, yogurt and soybeans.