OBSERVATIONS ON THE RENAL THRESHOLD FOR ASCORBIC ACID IN MAN

Abstract
Simultaneous estimations of the blood and urine levels of ascorbic acid were made in 2 groups of cases (1) a large miscellaneous group of patients and controls in which single observations were made and (2) a smaller group in which repeated observations were made at intervals following the oral or intraven. administration of a single test dose. The findings indicate that very little ascorbic acid is excreted in the urine when the blood level is below approximately 1.40 mg. per 100 ml. but that above this critical level it is excreted in maximal amts.