Hair grows anywhere from one-quarter to one-half inch per month. Several factors influence growth rate including genetics, diet. and lifestyle factors. Proper nutrition, according to MayoClinic.com, is crucial for hair growth as are adequate rest and exercise. Black hair is also prone to dryness and breakage, which makes it appear that the hair is growing slowly. Proper styling and maintenance keep the hair healthy, maintains the length and encourages growth. Diet and Lifestyle Step 1 Eat foods rich in protein and iron. According to MayoClinic.com, iron deficiencies contribute to hair loss. Red meat, beans and eggs are all rich in iron and protein. Dried fruits, whole grains and dark-green vegetables are also rich in iron. advertisement Step 2 Get your vitamins. Vitamins A, C and E, in addition to B vitamins, all contribute to hair growth. Eat foods rich in these vitamins, such as fresh fruits, vegetables and beans, or take a multivitamin to mee