DIETARY HABITS OF CALCIUM STONE FORMERS

1. Since dietary factors are known to be related to nephrolithiasis, c alcium stone-forming (CSF) patients were evaluated in terms of calcium , total protein of both animal and plant origin, carbohydrate and ener gy intakes, on the basis of 72-h dietary records during the week plus 24-h dietary records during the week-end. 2. The data for 77 calcium s tone formers (57 with absorptive hypercalciuria and 20 with renal hype rcalciuria) were compared to those for 29 age-matched healthy subjects . The body mass index of the CSF group was higher than that of healthy subjects (P<0.05). Consumption of all nutrients was similar for both groups during the week but week-end dietary records for CSF showed hig her calcium intake (586 +/- 38 vs 438 +/- 82 mg/day, P<0.05), protein to body weight ratio (1.2 +/- 0.1 vs 1.0 +/- 0.5 g kg-1 day-1, P<0.05) and animal protein (56 +/- 3 vs 40 +/- 3 g/day, P<0.05) when compared with healthy subjects. 3. Comparison of hypercalciuria subtypes (rena l hypercalciuria and absorptive hypercalciuria) did not indicate any d ifference in calcium or energy intake between groups, either during th e week or during the week-end. However, the absorptive hypercalciuric group presented higher protein and animal protein consumption during t he week-end. 4. These data suggest a low calcium intake in this popula tion, even by stone formers. The higher animal protein consumption by our calcium stone formers observed during week-ends seems to be more i mportant than calcium intake for stone formation.