Longevity tip: trim protein, not calories, new review suggests

A Cell Press Blue review of over 350 studies finds that restricting protein intake—without cutting total calories—may boost metabolism and cellular maintenance via the FGF21 hormone, offering a potential path to longer, healthier lives for sedentary adults. Active individuals still need protein for muscle, and the review cannot prove causation in humans; long-term, tailored protein guidelines by age and activity level are needed.