People in the US are still not getting enough vitamin C and the daily recommended dose for vitamin C should be doubled, according to Oregon researchers.
A higher intake of vitamin C may help prevent chronic diseases such as cancer, cardiovascular disease and cataracts, they note in the June issue of the American Journal of Clinical Nutrition. The current US recommended dietary allowance (RDA) is 60 milligrams per day (mg/day) for adult nonsmokers. However, this level is based on that needed — an average of 46 mg/day — to prevent scurvy, a vitamin C deficiency characterized by tooth loss, joint pain, and poor wound healing.
However, 90 to 100 mg of vitamin C per day could help prevent other chronic disease, according to Drs. Anitra C. Carr and Balz Frei, with the Linus Pauling Institute, Oregon State University in Corvallis.
Because the RDA of vitamin C is under revision by the National Academy of Sciences, they reviewed existing studies on the benefits of vitamin C in preventing a range of chronic diseases. The evidence “strongly suggests” that higher doses of vitamin C may be beneficial. “Therefore, we suggest that the RDA for vitamin C be doubled to 120 mg/day,” they conclude.
The recommendation is consistent with one made by Dr. Mark Levin, of the National Institutes of Health, Bethesda, Maryland, and colleagues in a recent article published in The Journal of the American Medical Association. As reported by Reuters Health in April, Levin’s group recommends increasing the RDA for vitamin C to between 100 and 200 mg/day.
The new analysis was funded in part by Roche Vitamins, Inc. and by the National Institutes of Health.
SOURCE: American Journal of Clinical Nutrition 1999;69:1086-1107.
Reprinted from www.excite.com, June 8, 1999