Nutritional risk factors in urinary stone disease.

The relationships between eating and drinking habits, and serum as well as 24-hour urinary concentrations of calcium, inorganic phosphate uric acid and urinary pH were studied in 379 patient in whom stones form. The 24-hour urinary calcium excretion was found to be increased in patients who preferably eat animal proteins and farinaceous foods (p less than 0.1). Regarding drinking habits, urinary calcium and inorganic phosphate excretion was found to increase significantly as a function of alcohol ingestion (p less than 0.01 and p less than 0.001, respectively). Similarly, an increased alcohol intake was found to be associated with higher serum uric acid concentrations (p less than 0.01). A significant increase in urinary pH was confined to patients preferably eating vegetables (p less than 0.005). The results of our study suggest alcohol consumption to be a potentiating factor for the risk of stone formation.