Review suggests lower protein intake may aid healthy aging in adults
A comprehensive review of over 350 studies indicates that reducing protein consumption, or limiting certain amino acids, could activate metabolic pathways linked to healthier aging, especially for sedentary adults who already meet recommended protein levels.
A review of more than 350 studies across humans, mice, insects and yeast, led by pathologist Dudley Lamming and published in Cell Press Blue, finds that consuming less protein—or limiting specific amino acids—may trigger hormonal and cellular processes associated with healthier aging and improved metabolism. The analysis notes that many adults already exceed the recommended daily intake of 0.8 grams of protein per kilogram of body weight, with typical meals providing 20 to 30 grams and national data showing average intakes of 79-82 grams per day.
"It's probably safe to say that for sedentary individuals, maybe [follow] the original [recommended daily amount of] 0.8 grams per kilogram," Lamming said.
The review highlights an increase in the hormone FGF21 when protein intake is reduced, which can boost energy expenditure and thermogenesis in adipose tissue, potentially leading to lower body fat and better blood-sugar control. It also suggests that lower protein may influence cellular signals that regulate growth, repair and recycling, processes that affect aging.
Experts caution that protein restriction differs from deficiency; the goal is to avoid excess rather than deprive the body of an essential nutrient. Needs vary: active adults, pregnant individuals, older adults, and those recovering from illness may require more protein, while people with kidney or liver disease should seek medical guidance. The authors acknowledge limitations, including varied study designs and a reliance on animal research, which may not fully translate to humans. They recommend that adults assess their actual protein requirements before adding extra high-protein products to their diet.