Hair is primarily made of protein, so it makes sense to eat protein-rich foods if you’re trying to maintain healthy growth. Without adequate protein intake, the body cannot efficiently make new hair to replace the hair that has shed. However, eating a steak every day isn’t going to help you. High-fat diets result in increased testosterone levels, which have been linked to hair loss—so steaks are not among the foods that prevent hair loss. Stick to leaner proteins such as fish (which has a myriad of health benefits beyond just maintaining your hair), chicken, soy products, low-fat cheese, eggs, almonds, beans and yogurt.