The exact nature of the saccharoid fraction (non-glucose reducing substances) in human blood is not known. The saccharoid fraction is increased in diabetic patients and a direct relationship exists to the height of the blood sugar. Some of the constituents of the saccharoid fraction, namely, glutathione, glucuronic acid and organic phosphate are significantly increased in diabetic patients. Fructose diphosphate and ATP are increased in the patients treated with oral hypoglycemic drugs. The known constituents of the saccharoid fraction which were determined accounted only for about 48% in normal and 36% in diabetic patients. The reduced contribution of these compounds to the saccharoid fraction in diabetic patients indicates that the nature of the saccharoid fraction may be different in diabetic patients.