Six women, aged 38 to 62 yr., participated in a 40-day metabolic study to investigate the effect of level of protein intake and of sodium bicarbonate ingestion on urinary calcium, net calcium balance, net renal acid excretion, and arterialized venous blood pH and bicarbonate ion concentration. The diet contained 44 g protein during the first 16 days and 102 g during the remaining 24 days. Calcium, phosphorus, and magnesium intakes were held constant at 500, 900, and 300 mg, respectively.
The increase in protein intake significantly increased urinary calcium and net renal acid excretion and the mean net calcium balance became negative
Calcium balance and acid-base status of women as affected by increased protein intake and by sodium bicarbonate ingestion