DEPARTMENT OF CHEMISTRY, STANFORD UNIVERSTY, STANFORD, CALIFORNIA 94305
The results of research on "Evolution and the Need for Ascorbic Acid" conducted by Linus Pauling (Linus Pauling, Evolution and the Need for Ascorbic Acid, PNAS 1970 67 (4) 1643-1648.).
Ascorbic acid differs from other vitamins in that an exogenous source is required by only a few animal species.
It is pointed out that this fact indicates that the amount contained in a diet of raw natural plant food is less than the optimum intake, corresponding to the best health. This argument leads to the conclusion that the optimum daily intake is about 2.3 g or more, for an adult with energy requirement 2500 kcal day-1.
The complete study "Evolution and the Need for Ascorbic Acid" (Linus Pauling) in pdf file format:
The original text taken from a:
Linus Pauling, Evolution and the Need for Ascorbic Acid, PNAS 1970 67 (4) 1643-1648.