Could eating too much protein speed up aging? New review raises questions
A review of 350 studies suggests lower protein intake may activate longevity pathways and support healthier aging
Could eating extra protein make you age faster? The question is gaining attention after a new review of more than 350 studies on protein restriction and aging suggested that consuming less protein may offer health and longevity benefits in certain populations.
For years, high-protein diets have been promoted for building muscle, supporting weight management, and improving overall health.
However, the comprehensive review suggests that while protein remains essential, many people may be consuming more than they need.
Protein-enriched products now line grocery store shelves, appearing in everything from cereal and coffee to bottled water.
As demand for high-protein foods continues to rise, researchers say the health benefits of excessive protein intake may be overstated.
The review indicates that lower protein intake may improve metabolism, reduce inflammation and cellular damage, and activate biological pathways associated with healthier aging and a longer lifespan.
The potential benefits appear to depend on factors such as age, overall health, and the source of dietary protein.
According to the researchers, high protein intake—particularly amino acids such as leucine, which is abundant in animal-based foods—can activate growth-related pathways including mTOR and IGF-1.
While these pathways play an important role in muscle growth and tissue repair, especially in younger or physically active individuals, persistent activation later in life may be associated with accelerated cellular aging and a higher risk of age-related diseases.
The review also suggests that reducing protein intake may increase levels of fibroblast growth factor 21 (FGF21), a hormone linked to improved blood sugar regulation, increased energy expenditure, and longer lifespan in experimental studies.
The researchers emphasized that protein restriction is not a one-size-fits-all recommendation.
Older adults, athletes, and people with certain medical conditions may have higher protein requirements, underscoring the importance of tailoring dietary intake to individual needs.
The review was supported by the U.S. National Institute on Aging, the Wisconsin Partnership Program, and the University of Wisconsin–Madison, and was published in the journal Cell Press Blue.
