Observations on the Amount of Ascorbic Acid Required to Maintain Tissue Saturation in Normal Adults

Abstract

Using a method for estimating the minimum intake of ascorbic acid required to maintain the tissues in a state of complete saturation as judged by urinary excretion of ascorbic acid, the requirement for three adult subjects was found to be from 1.6 to 1.7 mg. per kilogram per day. The urinary excretion was found to vary considerably for the same individual even under carefully controlled conditions of ascorbic acid intake. Values above 1 mg. of ascorbic acid per 100 ml. of blood plasma were obtained when the total daily intake was 60 mg.; more than 120 mg. daily were required to raise the blood plasma to 1.4 mg. The significance of the blood plasma levels in relation to saturation is discussed.