Vitamin B6 Depletion in Man: Urinary Taurine and Sulfate Excretion and Nitrogen Balance

Abstract

Six young men were fed a partially purified diet which supplied 0.16 mg of vitamin B₆ daily. When biochemical changes became apparent, the diet of each subject was supplemented with pyridoxine (0.6 or 0.9 mg). No clinical symptoms were noted which could be attributed to the vitamin B₆ depletion. The diet which was effective in producing the depletion was well accepted by the subjects and was adequate in all respects except for vitamin B₆; it contained 100 g of protein and was composed of casein, gelatin, rice, sucrose, jelly, carbonated beverages, selected fruits and vegetables low in vitamin B₆, a fat mixture which supplied 40% of the calories, L-methionine, and mineral and vitamin supplements. A 3.4-g loading dose of L-cysteine was administered orally several times during the study. At the height of vitamin B₆ depletion only one subject reflected the loading dose with an appreciably increased excretion of taurine, whereas, all subjects excreted increased amounts of taurine after the cysteine loading dose when their diets had been supplemented with pyridoxine. Urinary sulfate excretion after the cysteine loading dose and the nitrogen balance during the study were not affected by vitamin B₆ depletion or repletion.