Vitamins, including vitamin C, are organic compounds. An organic compound is one that exists in living things and contains the elements carbon and oxygen. Vitamin C is water soluble, and the body does not store it. To maintain adequate levels of vitamin C, humans need a daily intake of food that contains it. Vitamin C plays an important role in a number of bodily functions including the production of collagen, L-carnitine, and some neurotransmitters. It helps metabolize proteins and its antioxidant activity may reduce the risk of some cancers.