Categories of Functions of Vitamins
There are two categories of vitamins, water-soluble and fat-soluble vitamins. The fat-soluble vitamins include vitamins K, E, D, and A. These vitamins can dissolve in fats and get stored by the body. The water-soluble vitamins include the complex B vitamins (biotin, niacin, thiamin, folic acid, pantothenic acid, vitamin B12, and vitamin B6) and vitamin C.