Changes in Kidney Function Do Not Differ between Healthy Adults Consuming Higher- Compared with Lower- or...

Area of Science:

• Nutrition Science
• Nephrology
• Human Physiology

Background:

• Higher-protein (HP) diets are increasingly recommended for benefits like mitigating sarcopenia.
• However, the impact of HP diets on kidney function in healthy individuals remains unclear.
• This study addresses the need for clarity on HP diet effects on renal health.

Purpose of the Study:

• To conduct a systematic review and meta-analysis.
• To determine the effect of higher-protein (HP) intakes on kidney function in healthy adults.
• To compare HP diets with normal- or lower-protein (NLP) intakes.

Main Methods:

• Systematic review and meta-analysis of randomized controlled trials.
• Inclusion criteria: HP (≥1.5 g/kg/d or ≥20% energy) vs. NLP intakes, >4 days duration, adults without kidney disease.
• Searched Medline and EMBASE databases; analyzed glomerular filtration rate (GFR) using random-effects meta-analysis.

Main Results:

• Post-intervention GFR was slightly higher with HP diets (SMD: 0.19; P=0.002).
• However, the change in GFR from pre- to post-intervention did not differ significantly between HP and NLP groups (SMD: 0.11; P=0.16).
• A linear relationship was observed between protein intake and post-intervention GFR (r=0.332, P=0.03).

Conclusions:

• While post-intervention GFR may be higher with HP diets, the change in GFR is not significantly affected.
• HP intakes do not appear to adversely influence kidney function as measured by GFR in healthy adults.
• Further research may be needed to address potential selection bias in included trials.