Vitamins are essential substances needed by the body for proper growth and development. There are about 13 of them and each one plays important roles in health promotion. Examples are Vitamin A, Vitamin K, Vitamin D and the family of B Vitamins. In the Health Channel of Bright Hub are several articles that explains the effects of each of these vitamins inside the body. Other articles enumerate the different foods which are rich in a specific type of vitamin. Not only that, conditions that arise from lack or deficiency of these vitamins are also included, as well as their symptoms, diagnosis, treatment and prevention.