Reduced urinary protein after dietary protein restriction instruction in proteinuric diabetic patients.

An early restriction of dietary protein intake may reduce the rate of renal function deterioration in human diabetics. This study investigates the effect of a restricted-protein diet on proteinuria in diabetic patients with persistent albuminuria after frequent dietary instruction. Twenty-six patients were divided into two groups: the restricted-protein diet (RPD) group (16 patients), who were on a diet containing 0.6-0.8 g/kg/day protein; and the normal protein diet (NPD) group (10 patients), who were on a diet containing 1.5 g/kg/day protein. Weekly dietary interview were conducted by a dietitian and a trained nurse. Of the 26 patients studied, five RPD patients and three NPD patients were dismissed. Of the 11 RPD patients who completed the study, seven patients (RPD-success) had a decreased calculated protein intake (mean value, 62 +/- 4 g/day) compared to the corresponding value (mean value, 73 +/- 5 g/day) before the study. The mean calculated protein intake value in the RPD-success group was higher than the protein content (42 +/- 1 g/day) prescribed for them; however, that of the NPD group, did not significantly differ before and at the end of the study. The RPD-success group's daily urinary protein excretion showed a significant reduction, with a mean value before (1378 +/- 414 mg/day) and after (880 +/- 413 mg/day) 3.7 +/- 0.4 months dietary protein restriction. In contrast, the daily protein loss in the NPD group was insignificant (1300 +/- 443 to 2976 +/- 862 mg/day) after 3.3 +/- 0.6 months dietary instruction.(ABSTRACT TRUNCATED AT 250 WORDS)