Effects of Variations in Dietary Vitamin C on the Physical Well Being of Manual Workers

Abstract
If the previous diet has been good, total deprivation of vitamin C for 2 months does not lead in manual workers to detectable deterioration in physical vigor, to inefficiency in the day's work, or to unpleasant symptoms, provided the daily diet is adequate in all nutrients other than vitamin C. Such deprivation may occasionally lead to minimal changes in the gums, and does produce severe desaturation as measured by serum and urinary levels of vitamin C and by tolerance tests. When given in doses of 25 mg. 3 times daily, 75 mg. of ascorbic acid a day appear adequate to maintain or even to increase the body stores of the vitamin in a majority of men held for 2 months on a diet totally deficient in ascorbic acid. Supplements of 75 mg. of ascorbic acid a day when added to a good normal diet are of no detectable benefit to manual workers over a period of 2 months with respect to general well being, physical vigor for hard work, and efficiency in the day's work. Such supplements do lead to increased stores of vitamin C as evidenced by serum and urinary levels and by tolerance tests.