Long-term effect of modification of dietary protein intake on the progression of diabetic nephropathy: a randomised controlled trial

Abstract

Aims/hypothesis There is currently insufficient evidence to recommend a low-protein diet for type 2 diabetic patients with diabetic nephropathy. We assessed whether a low-protein diet could prevent the progression of diabetic nephropathy. Methods This was a multi-site parallel randomised controlled trial for prevention of diabetic nephropathy progression among 112 Japanese type 2 diabetic patients with overt nephropathy. It was conducted in Japan from 1 December 1997 to 30 April 2006. The participants were randomly assigned using a central computer-generated schedule to either low-protein diet (0.8 g kg) and normal-protein diet (1.2 g kg −1 day −1 ), and were followed for 5 years. The participants and investigators were not blinded to the assignment. The primary outcomes were the annual change in estimated GFR and creatinine clearance, the incidence of doubling of serum creatinine and the time to doubling of baseline serum creatinine.Other members of the Low-Protein Diet Study Group are listed in Electronic supplementary material Electronic supplementary material The online version of this article

A very-low-protein diet ameliorates advanced diabetic nephropathy through autophagy induction by suppression of the mTORC1 pathway in Wistar fatty rats, an animal model of type 2 diabetes and obesity

“…Regarding diet therapy, the efficacy of a low-protein diet (LPD) for advanced diabetic nephropathy remains controversial [2]. Previous clinical studies have not consistently shown beneficial effects of an LPD for the preservation of renal function in diabetic nephropathy [3][4][5][6][7][8].…”

“…Nezu et al showed that an LPD for diabetic nephropathy improves the estimated glomerular filtration rate when patients adhere to a protein-restricted diet [11]. However, LPD adherence is often poor [3,11], which has contributed to the controversial results of previous clinical studies. In addition, the amount of protein restriction would be expected to be important for renoprotection.…”

Referral to sub-specialists: who have the most to gain from early specialist intervention among patients with markers of renal disease?

“…[31][32][33][34] A low-protein diet has not reduced the risk of mortality or ESRD compared with a usual protein diet, at least in the course of CKD stages 1-3. [35][36][37][38][39] Screening for patients with chronic kidney disease stage 1-3: facts and fallacies…”

Paradigm Shifts in Nutrition Therapy for Type 2 Diabetes

“…24 In addition, an observational study of the general Japanese population showed that the higher-protein diet group had a lower odds ratio of chronic kidney disease, 25 and an intervention study did not prove the effectiveness of the low-protein diet. 26 Furthermore, the Modification of Diet in Renal Disease study, a famous randomized controlled trial in the United States, compared the low-protein diet and extremely low-protein diet in subjects with renal dysfunction and found that there was no significant difference in the time to end-stage renal failure (requiring hemodialysis or kidney transplantation) between the two diet groups, and that the extremely low-protein diet group had a higher mortality rate. 27 After the results were reported in 2009, Ikizler summarized the advantages and disadvantages of the low-protein diet; the details are shown in Table 2.…”