A sebum deficiency can cause dandruff, and excess vitamin A (through supplements) can cause hair loss. B-5 (pantothenic acid) nourishes hair follicles, promotes elasticity, strength and shine and helps prevent hair loss and graying. Find it in: kiwifruit, citrus fruits, peppers, blueberries, sweet potatoes, spinach, tomatoes, strawberries and broccoli. Find it in: blueberries, kiwifruit, tomatoes, spinach, walnuts, wheat germ, sunflower seeds, almonds, cabbage and avocados. Zinc helps build keratin and collagen, and iron helps red blood cells carry oxygen to the hair follicles.