New Low-Protein Diet with Methionine May Slow Aging and Boost Longevity

A new study has found that a low-protein diet enriched with methionine can extend the healthspan of aging organisms. The research, published in Cell Metabolism, was carried out by scientists from USC, the University of Toronto, and Harvard University. The longevity diet, called LDMM, draws inspiration from traditional Mediterranean eating patterns. It includes a carefully measured amount of the essential amino acid methionine. Mice on this diet lived longer, moved better, and showed less fat buildup and frailty compared to other groups.

Despite eating the same number of calories, LDMM mice lost fat mass while keeping their lean body mass intact. Their hormone levels also changed, with increases in growth hormone, GLP-1, and FGF21. These effects suggest the diet optimises metabolic health.

Human data supported these findings. People with plant-focused diets and moderated amino acid intake had lower rates of metabolic diseases. In contrast, high animal protein intake—linked to higher methionine—was associated with greater risks of obesity and Type 2 diabetes. The research team now plans to test the LDMM diet in human clinical trials. They aim to confirm its safety and effectiveness in improving healthspan. The findings could lead to dietary strategies that promote longer, healthier lives.