A modified Mediterranean-style diet low in protein but supplemented with methionine helped older mice stay healthier while eating more food. Researchers at the University of Southern California led the study, which also drew on human data linking lower animal protein intake to reduced obesity and diabetes rates. The findings were published in Cell Metabolism.
Scientists tested the diet on 20-month-old mice, comparing it with standard, Western, and ketogenic diets. Mice on the longevity diet showed longer healthspan, less body fat, and fewer frailty signs despite higher calorie intake.
The approach draws from traditional plant-centered Mediterranean eating patterns but adds controlled methionine levels from sources like eggs and dairy. Senior author Valter Longo noted that too little or too much of the amino acid eliminated benefits.
Analysis of dietary records from more than 200,000 people supported the pattern, with higher animal protein consumers facing twice the Type 2 diabetes risk. The team plans human clinical trials next.
