Abstract
Recommended daily allowances, U.S.A., for ascorbic acid are several times the minimum daily requirement of about 10 mg to prevent clinical symptoms in adults. The recommended daily allowances reflect the levels of ascorbic acid required to produce tissue saturation in human beings, so that higher doses are promptly excreted in the urine. In various investigations, responses to ascorbic acid were not obtained under conditions where the intake was considerably lower than the recommended daily allowances, but higher than the level needed to prevent clinical symptoms of ascorbic acid deficiency. The human ascorbic acid requirement cannot be calculated by a linear extrapolation from guinea pigs per kg of body weight because guinea pigs are much smaller than human beings and, hence, their metabolism is more rapid per unit of body weight. Evolutionary loss of ascorbic-acid-synthesizing ability may be a neutral change that was incorporated by genetic drift.
Keywords: ascorbic acid, diet
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Hodges R. E., Baker E. M., Hood J., Sauberlich H. E., March S. C. Experimental scurvy in man. Am J Clin Nutr. 1969 May;22(5):535–548. doi: 10.1093/ajcn/22.5.535. [DOI] [PubMed] [Google Scholar]
- Hodges R. E., Hood J., Canham J. E., Sauberlich H. E., Baker E. M. Clinical manifestations of ascorbic acid deficiency in man. Am J Clin Nutr. 1971 Apr;24(4):432–443. doi: 10.1093/ajcn/24.4.432. [DOI] [PubMed] [Google Scholar]
- King J. L., Jukes T. H. Non-Darwinian evolution. Science. 1969 May 16;164(3881):788–798. doi: 10.1126/science.164.3881.788. [DOI] [PubMed] [Google Scholar]
- Pauling L. Evolution and the need for ascorbic acid. Proc Natl Acad Sci U S A. 1970 Dec;67(4):1643–1648. doi: 10.1073/pnas.67.4.1643. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Yew M. L. "Recommended daily allowances" for vitamin C. Proc Natl Acad Sci U S A. 1973 Apr;70(4):969–972. doi: 10.1073/pnas.70.4.969. [DOI] [PMC free article] [PubMed] [Google Scholar]