Does low protein diet halt the progression of renal insufficiency?

We evaluated 15 adult patients with a mean creatinine clearance of 18.35 ml/min and a mean age of 45.7 years. Four patients had glomerulonephritis, two interstitial nephritis and nine had nephrosclerosis. Paired controls were used. Experimental patients were instructed in a diet with 0.55 grams of protein/kilogram body weight/day; the control group was on an unrestricted diet. Protein intake was evaluated with dietary histories. Protein catabolic rates were calculated and were used for reinforcement. Nutritional status was evaluated with anthropometric measurements and laboratory testing. Progression of renal insufficiency was estimated using the reciprocal of the serum creatinine. The mean follow up was 14.9 months. During this period, three patients started dialysis, four had their creatinine clearance remain stable and six improved their renal function 20%. The rate of change of renal function in the treatment group was slower (p < 0.05) than in the control group. Body weight, anthropometric measurements and chemical parameters did not change significantly. We conclude that a restricted protein diet stabilizes or improves renal function in most patients with end-stage renal failure without producing malnutrition.