Fish Fish makes any diet healthy, salmon is the fish for hair. This oily fish is rich in omega-3 fatty acids, Vitamin B12 and iron. Clubbed together, these components can restore the shine in your tresses. Omega-3 fatty acids are essential to retain a healthy scalp. A deficiency of omega-3 fatty acids can leave you with a dry scalp and dull, lifeless hair. Can’t get your hands on salmon? Substitute it with flaxseed instead.