High-Protein Nutrition in Critical Illness Found Ineffective, Study Reveals

In a groundbreaking study conducted by researchers at the University of Adelaide, findings reveal that enhanced protein nutrition does not yield improved outcomes for critically ill patients, contradicting previous assumptions about the benefits of high-protein diets in such medical contexts. The study was part of the TARGET Protein Trial, which included 3,397 patients from eight intensive care units (ICUs) in Australia and New Zealand. The participants were subjected to a randomized trial comparing a high-protein nutritional formula (100g/L) with a standard lower-protein formula (63g/L) over a twelve-month open-label crossover period.

According to Matthew Summers, a Ph.D. candidate and ICU research dietitian at the University of Adelaide, the research aimed to assess the impact of increased protein delivery on muscle loss during critical illness. "Increased protein delivery has the potential to attenuate muscle loss, but current international guidelines are based on low-quality evidence," Summers stated. Despite the high expectations surrounding protein supplementation, the study found no significant differences in the time patients spent outside the hospital or their health status three months post-intervention.

The trial also examined various secondary measurements, including duration of mechanical ventilation, length of ICU stay, and incidences of tracheostomy insertion. The results indicated that higher protein intake did not improve any of these outcomes. Furthermore, the study raised concerns about the potential risks associated with high-protein diets, particularly for patients suffering from acute kidney failure. "The higher protein formula was more likely to cause harmful outcomes in patients with acute kidney failure when they were admitted to ICU," Summers remarked, emphasizing the need for caution when providing increased protein to vulnerable patients.

Co-first author Lee-anne Chapple, a Senior ICU Dietitian and Research Fellow at the Adelaide Medical School, expressed the study's surprising nature. "While no benefit was found with higher protein delivery early in critical illness, this does not preclude the potential that higher protein delivery could be beneficial for patients during the recovery phase of critical illness," she noted. This finding indicates a need for further research to identify the optimal timing for protein interventions in recovery phases, aiming to inform future nutritional protocols in intensive care settings.

The implications of these findings are significant, as they challenge the long-held belief that higher protein intake unequivocally leads to better recovery outcomes in critically ill patients. The study's conclusions will likely influence clinical guidelines and practices surrounding nutritional interventions in ICUs, prompting health professionals to reconsider their approaches to dietary management in critical care settings.

The full study, titled "Augmented Enteral Protein During Critical Illness," was published in the Journal of the American Medical Association (JAMA) in July 2025. The research underscores an essential shift in understanding how nutrition impacts recovery in critically ill patients, emphasizing the necessity for evidence-based practices in healthcare.