ABSTRACT
Using the micromethod of Farmer and Abt, plasma vitamin C content of 9S boys and girls in a middle school was determined throughout the year 1954 to 1955. A dietary survey was also carried out every month of the year, for calculating the vitamin intake. The results of the present study are as follow:1. When the diet contains ample amount of fresh leafy vegetables in season, a satisfactory plasma vitamin C level can be maintained. When the diet is limited in fresh vegetables, plasma vitamin C readily decreases in those seasons.2. There is a significant seasonal variation of plasma vitamin C content Highest values are obtained in winter, the maximal content occurring in December. The minimal value is observed in June. This corresponds to the variation in the. level of vitamin C intake in different seasons. There is no significant difference between Autumn and Winter.3. No definite correlation between plasma vitamin C content and the condition of the gums was observed in the present study.4. The plasma vitamin C content of Chinese and English school children observed by some other authors was lower than that obtained in the present investigation. It is believed that the increase plasma vitamin C of the subjects in this study is mainly due to improvement of the living condition of the population and widespread education of the people in the fundamentals of nutritional science in recent years.