Microbial oxalate degradation: Effects on oxalate and calcium balance in humans

Abstract Three, 4-wk, controlled feeding periods were used to assess relationships between oxalate excretion, calcium balance, and numbers of oxalate-degrading bacteria during consumption of a baseline diet, and the baseline diet with the addition of 175 g spinach or 260 g broccoli by 8 premenopausal women. Oxalate intakes were 108, 100 and 1570 mg/day during consumption of the baseline, broccoli, and spinach diets, respectively. Numbers of oxalate-degrading bacteria (ODB) ranged from 10 6 –10 7 /g feces in 5 subjects whereas no oxalate-degrading bacteria (no-ODB) were detected in 3 subjects. Four of the 5 ODB subjects exhibited an increase (p