Why men die much younger than women: new insights

This is a very surprising discovery. Globally, men die on average 5.4 years earlier than women. The exact number of years varies somewhat from country to country, but is the same throughout the world and in many different cultures.

For example, in the United States, the mortality difference is 5.8 years in favor of women, and the main factors that cause men to die earlier than women are unintentional injury, diabetes, suicidemurder, heart disease (Yang and colleagues, 2024.).

New study understands why men die earlier than women from an evolutionary perspective

New study published in the journal October 1, 2025 scientific progress, To better understand why there is such a large mortality disparity between men and women, we used an evolutionary perspective (Stark and colleagues, 2025.). A study entitled “sexual The study “Selection drives sex differences in adult life expectancy in mammals and birds” focused on the question of whether differences in age at death between males and females are also observed in animals other than humans. To this end, scientists analyzed data on adult life expectancy from 528 species of mammals and 648 species of birds kept in zoos or living in the wild.

Like human males, males of other mammals often die younger than females of other mammals.

The findings for 528 mammal species were similar to those observed in humans. In 381 of 528 mammal species (72%), male animals died younger than female animals. Only 5% of the species had a mortality difference favoring males, but the remaining species showed no significant differences between male and female animals in terms of life expectancy. Nearly 40% of mammal species had very large differences in age at death favoring females. Across species, the difference in age at death between male and female mammals was 12% of their lifetime. Our closest primate relatives, chimpanzees and gorillas, had similar age differences at death, favoring females, as in humans. This shows that it is clearly the rule, rather than the exception, that males die younger than females in mammals. It also shows that differences in mortality are not unique to humans and may be partly the result of larger evolutionary patterns.

Interestingly, an opposite but weaker pattern was found for birds. Overall, 438 of 648 bird species (68%) showed mortality differentials favoring males. Across species, the difference in mortality between male and female birds was 5% over their lifetime.

How can the pattern of results be explained?

The scientists then performed further statistical analysis to explain this pattern of results.

The factor that explained most of the pattern of results was whether the species was monogamous or non-monogamous. For example, in non-monogamous species living in zoos, female lifetimes increased by 15% compared to males. In monogamous species, there was little difference in age at death. This finding is consistent with the so-called sexual selection hypothesis, which suggests that males may exhibit risky behaviors (e.g., fighting other males) that may jeopardize their survival in order to mate with females. This effect is particularly pronounced in non-monogamous species. In these species, competition Relationships between males are more intense than in monogamous species, leading to more risky behavior and early death.

A second factor that partially explained the results was the difference in size between male and female animals. Larger differences in age at death occurred in species where male animals were much larger than female animals. This finding is consistent with the original discovery, as species with very large size differences between males and females (think gorillas and walruses) are often non-monogamous.

Furthermore, women’s care for their offspring was a contributing factor to the age difference. In general, parents tend to take fewer risks because they are responsible for their children, which may explain why parenthood increases life expectancy.

What do the findings tell us about why men die much younger than women?

The scientists suggested that their findings may help explain why there is such a strong and consistent difference in life expectancy between men and women. The female advantage in life span length is not unique to humans, but is part of a broader pattern in mammalian evolution. Men are known to engage in more risky behaviors than women, such as driving at high speeds and drinking alcohol. alcoholor drugs may shorten your lifespan.

Many of the factors listed above that contribute to age differences at death (unintentional injury, diabetes, suicide, homicide, heart disease) can be positively influenced by lifestyle choices. This study suggests that caring for offspring reduces risky behavior and increases lifespan, so becoming a father could be a great way to narrow the gap in age at death.