METHIONINE ↑ RED MEAT Restricting the amino acid methionine in the diet provides many of the health and longevity benefits of calorie restriction (at least in mice). The detailed mechanism of methionine-related liver damage and cardiovascular toxicity are poorly understood but do occur with high rates of methionine ingestion. Diet affects your long term prospects for health and degenerative aging illnesses on a sliding scale that is measured in calories and methionine intake.