Why do women outlive men?

Around the world, women live longer than men [Ortiz-Ospina & Beltekian 2018]. This is true not only for humans, but also for many other mammalian species [Xirocostas et al. 2020]. The higher life expectancy of women is often attributed to the fact that women generally eat healthier and pay more attention to their health. On average, women visit the doctor earlier and more often than men, generally drink less alcohol, use less tobacco and pay more attention to a healthy diet [Griswold et al. 2018, Oksuzyan et al. 2014]. Life expectancy statistics also include suicide, which is significantly more common in men than in women [Kiely et al. 2019, Miranda-Mendizabal et al. 2019]. However, there may also be a genetic component that makes women live longer. The advantage for women may be the double X chromosome [Xirocostas et al. 2020]. While women have two X chromosomes, men have one X chromosome and one Y chromosome. Important genetic information on the X chromosome is therefore duplicated in women and can compensate for possible gene mutations and defects on the other X chromosome.

This is not the case in men and is responsible, for example, for the colour blindness that is much more common in men. A key factor in ageing may be that the X chromosome also contains gene segments that influence the body's immune system [Libert et al. 2010]. If these gene segments are defective in men, they cannot be compensated for by a second, defect-free X chromosome. In addition to the different sex chromosomes, the influence of sex-specific hormones on the ageing process is also being discussed. For example, the hormone testosterone has been linked to risk-taking behaviour and an increased incidence of cardiovascular disease in men [Roberts et al. 2004, Stanton et al. 2011].

More FAQs on ageing

References:

• Ortiz-Ospina E, Beltekian D (2018) Why do women live longer than men? Our World in Data
• Xirocostas ZA, Everingham SE, Moles AT (2020) The sex with the reduced sex chromosome dies earlier: a comparison across the tree of life. Biol Lett 16(3):20190867.
• Collaborators GBDA (2018) Alcohol use and burden for 195 countries and territories, 1990-2016: a systematic analysis for the Global Burden of Disease Study 2016. Lancet 392(10152):1015-1035.
• Oksuzyan A, Shkolnikova M, Vaupel JW, Christensen K, Shkolnikov VM (2014) Sex differences in health and mortality in Moscow and Denmark. Eur J Epidemiol 29(4):243-252.
• Kiely KM, Brady B, Byles J (2019) Gender, mental health and ageing. Maturitas 129(76-84)
• Miranda-Mendizabal A, Castellvi P, Pares-Badell O, Alayo I, Almenara J, Alonso I, Blasco MJ, Cebria A, et al. (2019) Gender differences in suicidal behavior in adolescents and young adults: systematic review and meta-analysis of longitudinal studies. Int J Public Health 64:265-283.
• Libert C, Dejager L, Pinheiro I (2010), The X chromosome in immune functions: when a chromosome makes the difference. Nat Rev Immunol 10:594-604.
• Roberts ML, Buchanan KL, Evans MR (2004) Testing the immunocompetence handicap hypothesis: a review of the evidence. Animal Behaviour 68(2):227-239.
• Stanton SJ, Liening SH, Schultheiss OC (2011) Testosterone is positively associated with risk taking in the Iowa Gambling Task. Horm Behav 59(2):252-256.