Men die, women suffer

It is well known that men die earlier than women. The sad part is that women live longer than men, but in worse health1, a trend that exists across many different countries2. If we can understand why, we can do something about it. Can we get women to live with the health benefits of men, and men to live as long as women?

Turning to evolution to help explain this difference, we can start to understand why. Evolution comes down to fitness, and fitness comes down to passing on your genes. The first issue then is that men can reproduce for most of their lives, even at very old ages, while women at some point stop. Therefore, if there is a gene that would be good when in a man’s body but bad when in a woman’s body, it might actually be selected for by evolution, since men can have more offspring than women even into advanced ages. So having men be healthier but die sooner could help them have more children, while this wouldn’t be as important for women. Women of course, have a powerful card called ‘the grandmother effect,’ which gives them a very important reason to stick around, so whatever gene the men might be slipping into the human genome can’t be so bad that it completely kills off women after reproduction. The result? Men die, women suffer.

This evolution theory seems to be exactly what’s happening. Scientists performed a lab-based evolutionary experiment in flies, where they only allowed older and older males to reproduce, generation after generation. This was to select for genes that would make the males be healthier into old age. The result after many generations of selection? Older female flies had worse health3. Now we need to find the genes. And then figure out if the same ones are affecting humans. Most likely – they are. As the scientists of the study pointed out, in humans, ‘masculinity’ in men makes for better health, while ‘masculinity’ in females leads to poorer health during aging.

One important question comes up now: if our bodies age differently depending on our gender, will ‘longevity drugs’ act differently for each gender too? Scientists only have a handful of drugs in the lab that can extend lifespan in mice. Of these, we already know there are major differences depending on the gender4: Giving mice compounds such as aspirin, nordihydroguaiaretic acid (NDGA), acarbose, or 17-α-estradiol, will extend lifespan preferentially in males and less or not at all in females. Giving mice interventions that slow ‘growth’ pathways including IGF-1 or mTOR benefit both genders, but females much more so. Medicine is only at the start of gender equality in drug development, and in the longevity-science field too. The good part though is that achieving gender equality in longevity-science will come from science, not history or politics, and has the potential to give all humans the longevity of women and the health of men.

Going deeper…

Oksuzyan A, Juel K, Vaupel J, Christensen K. Men: good health and high mortality. Sex differences in health and aging. Aging Clin Exp Res. 2008;20(2):91-102. [PubMed]
Jagger C, Gillies C, Moscone F, et al. Inequalities in healthy life years in the 25 countries of the European Union in 2005: a cross-national meta-regression analysis. The Lancet. 2008;372(9656):2124-2131. doi: 101016/s0140-6736(08)61594-9 [Source]
Archer CR, Recker M, Duffy E, Hosken DJ. Data from: Intralocus sexual conflict can resolve the male-female health-survival paradox. 2018. doi: 10.5061/dryadp888tv2 [Source]
Austad SN, Bartke A. Sex Differences in Longevity and in Responses to Anti-Aging Interventions: A Mini-Review. Gerontology. 2015;62(1):40-46. doi: 101159/000381472
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