Lowering protein intake may extend lifespan, new review suggests

A comprehensive review published in Cell Press Blue analyzed more than 350 prior studies and reported that high protein consumption can diminish longevity, whereas low-protein diets extend it in rodents. Mice receiving only 5-8% of calories from protein lived up to 53% longer, showing less frailty, lower cancer incidence, and reduced fat stores. The researchers attribute these benefits to higher levels of the hormone FGF21, which stimulates metabolic pathways that burn fat.

Parallel work in Nature Aging showed that limiting the amino acid valine increased median mouse lifespan by 23%. Scientists caution that protein remains essential for muscle and organ maintenance, but excess beyond basic needs may be converted to fat or waste, potentially harming health. While the findings stem mainly from animal work, the similarity in protein requirements between mice and humans suggests possible relevance, especially for sedentary populations.