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Published on: April 11, 2014
Determination of optimal vitamin C requirements in humans
M Levine1, K R Dhariwal, R W Welch
1Laboratory of Cell Biology and Genetics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0850, USA.
Abstract:
Although the recommended dietary allowance provides an estimate for vitamin C ingestion in humans, optimal vitamin C requirements are unknown. We define optimal vitamin C requirements operationally based on the following: dose-function relations, availability in the food supply, steady state concentrations in plasma and tissues achieved at each dose of vitamin C, urinary excretion, bioavailability, toxicity, and epidemiologic observations. Optimal vitamin C requirements can be estimated when information is available for at least some of these criteria.
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