Severe dietary protein restriction in overt diabetic nephropathy: benefits or risks?

J Ren Nutr. 2002 Apr;12(2):96-101. doi: 10.1053/jren.2002.31762.


Objective: To evaluate whether restricting protein intake may delay the progression of chronic renal failure caused by overt diabetic nephropathy and also whether this increases the risk of malnutrition.

Design: Prospective clinical trial.

Setting: Nephrology outpatients.

Patients: Sixty-nine patients (32 affected by type 1 and 37 by type 2 diabetes, all treated with insulin) affected by both overt diabetic nephropathy and hypertension.

Intervention: The study was started once hypertension and glycemia had been under control for at least 3 months. Two groups of patients, matched for similar mean glomerular filtration rate value and nutritional status, were studied: a low-protein diet (0.6 g/kg/d) was randomly prescribed to 35 patients, whereas in the other 34 patients a free diet intake was maintained for 12 months.

Main outcome measure: Renal function and nutritional status.

Results: The protein intake was significantly different in the 2 groups of patients, whereas the average decline of glomerular filtration rate during the follow-up was comparable. In the low-protein diet group, serum prealbumin concentration significantly decreased after 9 months, whereas serum albumin decreased at the end of the study.

Conclusion: Severe dietary protein restriction does not seem to delay the progression of renal disease in patients with overt diabetic nephropathy, whereas it may induce malnutrition.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Aged
  • Diabetic Nephropathies / diet therapy*
  • Diet, Protein-Restricted*
  • Dietary Proteins / administration & dosage*
  • Female
  • Humans
  • Kidney / physiopathology*
  • Kidney Failure, Chronic / diet therapy*
  • Male
  • Middle Aged
  • Nutrition Disorders / etiology*
  • Nutritional Status / physiology
  • Prospective Studies
  • Risk Factors


  • Dietary Proteins