EFFECT OF OAT BRAN MUFFINS ON CALCIUM-ABSORPTION AND CALCIUM, PHOSPHORUS, MAGNESIUM AND ZINC BALANCE IN MEN

Metabolic balance studies were conducted in adult human males to investigate the effect of oat bran on the nitrogen, calcium, phosphorus, magnesium and zinc balance, on the intestinal absorption of calcium and on the endogenous fecal calcium, using 47CaCl2 as the tracer. A 40-d control period preceded a 32-d experimental period in which subjects consumed four oat bran muffins daily as part of a constant metabolic diet. No significant changes in the calcium, magnesium or zinc balances were observed, but the nitrogen and phosphorus balances increased. The net or apparent absorption of nitrogen, magnesium and phosphorus expressed per milligram of intake increased significantly in the oat bran period due to the added content of these nutrients in the oat bran muffins. The intake of the oat bran muffins led to a significant increase in urinary phosphorus and significant decreases in urinary calcium and 47Ca excretions. The intestinal absorption of calcium, determined with 47Ca, did not change, whereas the endogenous fecal calcium increased slightly but significantly.