"Recommended daily allowances" for vitamin C.

Although 41 years have elapsed since the identification of vitamin C, the amounts required for human health are far from established. Pauling's suggestion that human needs for this vitamin probably have been underestimated by a factor of 10 or more has frequently been ignored or refuted by rhetoric rather than by sound experimentation. In the present study young healthy guinea pigs were fed a scrobutic diet supplemented with ascorbic acid at four widely different levels (0.05, 0.5, 5.0, and 50 mg/100 g of body weight per day). Growth rates both before and after surgical stress, recovery times after anesthesia, scab formation, wound healing, and the production of hydroxyproline and hydroxylysine during wound healing all support the conclusion that young guinea pigs ordinarily need about 5.0 mg/100 g of body weight daily. This is far beyond what is needed to prevent scurvy. Under stress the needs are even higher. On a body-weight basis this amount is equivalent to a need on the part of a 30-kg human child of 1500 mg of ascorbic acid daily. While calculations on a body-weight basis are subject to some uncertainty, the enormous discrepancy (nearly 40-fold) between this amount and that recommended by the Food and Nutrition Board calls attention to the extreme uncertainty about human ascorbic-acid needs, and to an important public health problem related to the best development of young people.