Objective: To determine whether low protein diets retard the development of end stage renal disease.
Design: Meta-analysis of 46 trials since 1975, from which six randomised controlled trials were selected.
Setting: Five trials in Europe and one in Australia between 1982 and 1991.
Subjects: 890 patients with mild to severe chronic renal failure who were followed up for at least one year. 450 patients received a low protein diet and 440 a control diet.
Intervention: Difference in protein intake between control and treated groups of at least 0.2 g protein/kg/day.
Main outcome measure: Number of renal deaths (the necessity to start dialysis or death of patient during study).
Results: 156 renal deaths were recorded, 61 in the low protein diet group and 95 in the control group, leading to an odds ratio of low protein to control of 0.54 with a 95% confidence interval of 0.37 to 0.79.
Conclusions: This result, obtained on a large population of patients suffering from chronic renal insufficiency, strongly supports the effectiveness of low protein diets in delaying the onset of end stage renal disease.