The Minimum Ascorbic Acid Need of Adults

Abstract

The daily vitamin C requirements of seventy-one male prisoners were investigated over a period of 17 months. Oral disease was prevalent among the younger as well as the older subjects. The daily food lists revealed that no fresh fruit and very few fresh vegetables were included in the diet. Laboratory results of plasma ascorbic acid determinations in untreated individuals showed that only a very few men, who were securing oranges or vitamin preparations for themselves, had plasma values over 0.6 mg. %; nearly 80% were under 0.2 mg. %, and twenty out of seventy-one showed no ascorbic acid in the plasma. Figures were very slightly higher in August and September than during the rest of the year. Results of ascorbic acid supplements on plasma and gums were as follows: 25 mg. daily gave no significant elevation of the plasma values and only slight improvement in the gum disease; 50 mg. raised the plasma values noticeably, and definite improvement was noted in the gums, but this amount was not sufficient to maintain a plasma level of 0.8 mg. % during the winter and spring months. With a 75 or 100 mg. supplement the most satisfactory response of both plasma and gum healing was obtained. The 75 mg. also appeared sufficient for most of the men throughout the year. The few cases refractory to 75 mg. responded to an increase in dosage (100 mg.) within 4 to 5 weeks.