Evidence check: MC4R in the context of longevity

MC4R (melanocortin 4 receptor) is a key regulator of energy homeostasis and appetite. Mutations in MC4R are the most common cause of monogenic obesity. However, a direct link to longevity is not well established. While obesity is a risk factor for reduced lifespan, the effects of individual MC4R variants on longevity are small and population-dependent. Existing studies focus on metabolism and weight, not lifespan. Consumer DNA tests that analyze MC4R in the context of longevity often overstate clinical relevance. The evidence is mixed: strong for weight regulation, weak for direct longevity. Lifestyle factors dominate. Be cautious of exaggerated claims.