7. Vitamin D
Also called cholecalciferol, Vitamin D is a steroid vitamin, a group of fat-soluble prohormones, which encourages the absorption and metabolism of calcium and phosphorous. People who are exposed to normal quantities of sunlight do not need vitamin D supplements because sunlight promotes sufficient vitamin D synthesis in the skin. It is also important in the maintenance of strong and healthy bones and a deficiency of this vitamin can cause you to have osteoporosis. You can get this vitamin by exposing yourself to early-morning sunlight, and eating fish and vitamin-fortified products.