Vitamin C or ascorbic acid is perhaps the most commonly known and used of all the vitamins, but few really know the immense variety of health benefits associated with it. Ascorbic acid is a water-soluble vitamin which is necessary in the body to form collagen in bones, cartilage, muscle, and blood vessels. Dietary sources of vitamin C include fruits and vegetables, mostly citrus fruits such as lemon and oranges. Vitamin C is an anti-oxidant.