why do women outlive men

Women tend to outlive men due to a combination of genetic, biological, behavioral, and evolutionary factors. Genetically, women have two X chromosomes while men have one X and one Y chromosome, giving women a backup copy of many important genes that can protect against certain genetic defects and enhance immune function. Biologically, hormones like estrogen in women provide protective effects such as reducing harmful cholesterol and supporting stronger immune responses, while testosterone in men has been linked to riskier behavior and higher rates of cardiovascular disease. Behaviorally, women are more likely to adopt healthier lifestyles, including better diets, less tobacco and alcohol use, and more frequent health monitoring. Evolutionarily, in many mammal species females live longer than males due to sexual selection and parental investment strategies that may favor female longevity. Additionally, men exhibit higher mortality from suicide and risky behaviors, which contribute to the lifespan gap. This pattern is evident not only in humans but across many mammalian species, suggesting a deep-rooted biological and evolutionary basis for the difference in lifespan between sexes. In summary, women live longer than men because of the protective genetic advantage of two X chromosomes, beneficial effects of female hormones, healthier lifestyle tendencies, and evolutionary factors that favor females' longevity and survival across species.