Population-wide recommendations to increase protein intake to 1.2–1.6 g/kg/day lack robust long-term evidence for health benefits in healthy adults, and these recommendations risk overextending findings from subgroups such as older adults or individuals in weight-loss interventions, where higher protein intake has not been shown to reduce morbidity or mortality in the general population.

When healthy adults consume more protein than their body needs, the extra amino acids are broken down and converted into waste products that the liver and kidneys must process. This increases the workload on these organs without providing any additional benefit for longevity or disease prevention. The body does not store excess protein as muscle unless there is a specific demand, such as from exercise or aging, and in healthy people without those demands, the extra protein simply adds metabolic stress without improving health.