Absorption of vitamin C: In human and guinea pigs, the absorption of vitamin C occurs in the buccal mucosa,stomach and the small intestine. The buccal absorption of vitamin C is mediated by passive diffusion through the membrane of the buccal cavity. While gastrointestinal absorption is through an efficient and an active sodium dependent, energy-requiring and carrier-mediated transport mechanism (Stevenson, 1974). Gabby and Singh (1991) have also explained the absorption of vitamin C through an active transport system located in the gut and its re-absorption in the kidneys. Since the absorption mechanism in the gut and kidney can reach a saturation point, it is better to take multiple and smaller doses of vitamin C through out the day than one large dose. At higher intakes, the process is saturated; up to 180 mg, there is an average absorption of 70% in both smokers and non-smokers, but absorption decreases from 50 to 16% at intakes over the range of 1.5-12 g (Kublr and Gehler , 1970).