Myths vs facts: MC4R and longevity

MC4R (melanocortin-4 receptor) is a key regulator of appetite and energy balance. A common myth is that MC4R variants directly determine lifespan. In reality, MC4R polymorphisms are associated with obesity and increased hunger, and obesity indirectly raises the risk of cardiovascular disease, diabetes, and premature mortality. However, this is a correlational, not causal, link to longevity. Evidence comes from GWAS and mechanistic studies, not from direct longevity trials. Effect sizes are small, and a single MC4R test cannot predict life expectancy. Consumer DNA tests often overstate such associations. For genuine longevity benefits, focus on diet, exercise, and regular health screenings rather than isolated genetic markers.