Hair normally grows at the rate of about 1/2 inch per month (6 inches per year). With age, that growth can slow to 1/10th of an inch per month. You can maximize your hair’s genetic growth cycle by including amino acids and B-vitamins in your diet. Protein (since hair is a protein) is also important for hair growth. Avoiding stress and taking care of the hair you have with hot oil treatments and limiting heat and pulling will keep it healthier.