Walnuts are the only type of nut that have a significant amount of omega-3 fatty acids. They’re also rich in biotin and vitamin E, which helps protect your cells from DNA damage.
Sweet potatoes are a great source of the antioxidant beta carotene, which your body turns into vitamin A. Basically, every cell of the body cannot function without enough A. It also helps protect and produce the oils that sustain your scalp, and being low on vitamin A can even leave you with itchy, irksome dandruff.