Acute Effects of Dietary Protein on Calcium Metabolism in Patients with Osteoporosis1.

Five untreated osteoporotic patients were studied in a metabolic unit for 30 days while receiving control (0.8 gm/kg) and high (2.0 gm/kg) protein diets of purified proteins. The high protein diet increased urinary calcium and produced a negative calcium balance without causing significant change in calcium absorption, serum chemical values, or urinary sodium and potassium. Variable effects of calcium and/or estrogens were found on the negative balance. Hence, increased dietary protein acutely causes a negative calcium balance in osteoporotic patients and may contribute to bone loss in this disease. [ABSTRACT FROM PUBLISHER]