Reduced Protein Consumption Linked to Better Health and Longer Lifespan: Study - Video

While protein-enriched foods are becoming increasingly popular, a new review published in Cell Press Blue suggests that consuming less protein may offer important health benefits for many people, particularly those who are relatively inactive. The review analyzed more than 350 studies on protein restriction and aging.

Researchers found that reducing protein intake may slow biological aging by improving metabolism, lowering inflammation, reducing cellular damage, and preserving healthy cell function. Unlike calorie restriction, which can be difficult to maintain, protein restriction has shown benefits in animal studies without reducing overall calorie intake.

Previous research has demonstrated that lower protein intake can extend lifespan in flies and rodents. Human clinical trials have also found that protein-restricted diets can reduce body weight, fat mass, and fasting blood sugar, even when participants consume more total calories.

One of the main biological mechanisms involves fibroblast growth factor 21 (FGF21), a hormone that rises when protein intake is low. Higher FGF21 levels have been linked to increased energy expenditure, improved blood sugar regulation, and reduced inflammation. Studies in mice have also associated elevated FGF21 with longer lifespan.

The review further highlights specific amino acids—including methionine, isoleucine, and valine—that may contribute to aging-related processes when consumed in excess. High intake of these amino acids may stimulate growth-related pathways that increase the risk of obesity, chronic inflammation, and other age-related diseases.

The authors note that protein requirements are not the same for everyone. Pregnant women, highly active individuals, and some older adults may require higher protein intake. However, many sedentary adults already consume more protein than necessary and may not benefit from protein-fortified foods.

Although the review supports the potential benefits of moderate protein restriction for healthy aging, it does not recommend that everyone reduce protein intake. The authors emphasize that protein recommendations should be personalized based on factors such as age, health status, and physical activity, rather than applying a one-size-fits-all approach.

REFERENCE: Bailey A. Knopf, Dudley W. Lamming; The Hallmarks of Protein and Amino Acid Restriction in Aging and Longevity. Cell Press Blue. DOI: 10.1016/j.cpblue.2026.100079.