Low-protein diet lowers urinary urea, glucose levels

Low-protein diets appear to have beneficial effects on cardiovascular risk factors and kidney function in patients with diabetic nephropathy, with a recent study showing that such diets produce a significant reduction in urinary urea and blood sugar.

Researchers conducted a systematic review and meta-analysis of randomized controlled trials that evaluated the efficacy of low-protein diets on cardiovascular risk factors and kidney function in patients with diabetic nephropathy. They searched multiple online databases for relevant studies without using time or language restrictions.

Pooled data showed that individuals with a low-protein diet had markedly lower urinary urea (weighted mean difference [WMD], –244.49 g/day, 95 percent confidence interval [CI], –418.83 to –70.16; p=0.006) and HbA1c (WMD, –0.20, 95 percent CI, –0.39 to –0.01; p=0.036) levels.

There were no significant or favourable effects seen on other renal function parameters and cardiovascular risk factors.

Of note, the results of subgroup analysis showed that low-protein diets led to a further decrease in HbA1c in intervention studies with a follow-up period of ≤24 weeks, when protein intake was <0.8 g/kg/d, and among individuals aged <50 years.

In the group of diabetic nephropathy patients aged <50 years who had type 1 diabetes, following a low-protein diet resulted in a substantial reduction in albuminuria.