Men Keep Dying Sooner Than Women, But Why?

The answer could lie in behavioral differences, immune systems, or genetics

Photo Illustration: R. A. Di Ieso
Nov 22, 2016 at 10:00 AM ET



“If we know that men in the 21st century can live way longer than women in the 18th century, why haven’t they caught up to women?” Duke University biologist and study co-author Susan Alberts told Vocativ. “If we could figure out why there is a difference, we could intervene potentially to mitigate. But we don’t know. It’s a puzzle.”


Another hypothesis, according to Alberts, is that females have more effective immune systems — either because higher testosterone in males potentially suppress male immunity or as a byproduct of evolution’s emphasis on the female reproductive role. “You’ve got to have a great immune system to have babies,” she said.

The final possible explanation lies in primate genetics. Women have two X chromosomes, while men have one X and one Y. In this theory, women live longer because they have a backup X chromosome that can guard against harmful mutations on one of the chromosomes. That’s unlikely, however, since one of a woman’s two X chromosomes is actually inactive. “Even though we have two X chromosomes, one of them is mostly asleep most of the time,” she said.

More Women Are Achieving Equality With Men… In How Much They Drink



Yet, even then, when disease and hardship ravaged the Liberian population so that just reaching one’s third birthday was a minor miracle, girls still lived longer than boys, and the relative gap in life expectancy was in line with that of all the other human and primate populations. This is indeed a puzzle, and solving it could unlock something buried deep in our evolutionary history.