Very Low Protein Intake Linked to More Kidney Failure and Deaths in Adults With Kidney Disease

The work is an observational study in people, published in JAMA Network Open on October 22, 2026. It followed 1,861 adults with chronic kidney disease (CKD) who were not on dialysis. They were enrolled between 2011 and 2016 at nine tertiary hospitals in South Korea, and followed for a median of 9.3 years. Their mean age was 53.7.

The researchers did not rely on food diaries. They estimated each person's daily protein intake from a 24-hour urine collection at the start of the study, using the nitrogen in the urine. They sorted participants into five groups, from less than 0.6 grams of protein per kilogram of ideal body weight per day to 1.2 or more. The main outcome was kidney failure requiring dialysis or a transplant. Death from any cause and major cardiovascular events were secondary outcomes.

The authors concluded that low protein intake was not associated with significant kidney protection. It was associated with a higher risk of kidney failure and of death. They also saw a nonlinear pattern, in which excessively low intake went with a higher risk of kidney failure.

The primary paper gives the figures. In the fully adjusted analysis, people eating less than 0.6 g/kg/day had a 42% higher subdistribution hazard of kidney failure than those eating 1.2 or more (subdistribution hazard ratio 1.42; 95% CI 1.09–1.85). The reported mortality hazard estimate was 2.17 (95% CI 1.17–4.03). These relative hazard measures are not percentage-point changes in an individual's chance of an event. Major cardiovascular events did not differ significantly between groups.

The primary paper also reports that the kidney finding held when the team excluded anyone who reached kidney failure in the first year, and anyone with signs of poor nutrition. It held again in a matched comparison (1.52; 95% CI 1.11–2.08). The authors' concern is protein-energy wasting, a loss of muscle and nutritional balance that is common in CKD. They say strict restriction may worsen it, especially in people with less muscle to spare.

The study's introduction notes that 0.6 to 0.8 g/kg a day has long been advocated for non-dialysis CKD. Clinical guidance has since diverged. The 2020 KDOQI guideline recommends 0.55 to 0.60 g/kg/day for metabolically stable adults with stages 3 to 5 CKD and no diabetes, under close clinical supervision. The 2024 KDIGO guideline suggests 0.8 g/kg/day for stages 3 to 5. It also advises against intake above 1.3 g/kg/day in adults at risk of CKD progression, while allowing selected supplemented very-low-protein regimens under close supervision. The authors say their results support this move toward more normal protein intake, and they call for individualized dietary management that weighs nutritional status and body composition.

For families, restriction should be balanced with nutritional monitoring and an individualized plan from the renal dietitian or nephrology team. This observational study cannot show that raising protein intake prevents kidney failure. Protein was estimated from one baseline urine collection, and the analysis could not account for total calories or protein source. Do not change a prescribed kidney diet on the basis of this study alone.

What to watch next is whether other cohorts, including those outside Korea, find the same pattern at the lowest protein intakes.

Sources: Suh and colleagues, JAMA Network Open, October 22, 2026. KDIGO 2024 guideline executive summary.