In a study on longevity in 121 countries, women tended to outlive men by about 5 years . The suggested causes for this are numerous, some of which are temporally, geographically, or culturally specific.
On the terminology, sex tends to refer to the absolute biological differences, whereas gender relates more to differences in perception/lifestyle (for instance, socio-economic differences).
In a study on Greek centenarians the authors found that women outnumbered men (1.68:1), with men having a higher likelihood of smoking, and thus are more at risk of smoking-related illness and mortality (historically this was more true than today) . This is also true for alcohol consumption. The authors also report that having a first degree relative who was also a centenarian is associated with longevity (highlighting the importance of genetic factors in lifespan determination).
There is also evidence that the rate of telomere shortening (number of cell-divisions until cell-cycle arrest) is sex-specific .
rwst cites an interesting paper, that presents evidence that suggests male hormones may decrease lifespan . This may be due to differential onset of atherosclerosis and cardiovascular disease, caused by exposure to different sex hormones .
In a review on the brain/behaviour specific aspects of differential ageing between the sexes, the authors discuss differences in brain anatomy and cognitive (and emotional) functionality between the sexes .
This is by no means an exhaustive list of the reasons for differences in lifespan between the sexes in humans. There are likely to be many other causes, such as men tending to have more 'risky' behaviours, and possibly other unknown genetic effects, such as having 2 X chromosomes, vs. XY.
- Møller, A. P., et al (2009). Why men have shorter lives than women: effects of resource availability, infectious disease, and senescence. American journal of human biology : the official journal of the Human Biology Council, 21(3), 357-64. doi:10.1002/ajhb.20879
- Tigani, X., et al (2011). Gender differences in Greek centenarians. A cross-sectional nation-wide study, examining multiple socio-demographic and personality factors and health locus of control. BMC geriatrics, 11, 87. doi:10.1186/1471-2318-11-87
- Barrett, E. L. B., & Richardson, D. S. (2011). Sex differences in telomeres and lifespan. Aging cell, 10(6), 913-21. doi:10.1111/j.1474-9726.2011.00741.x
- Min, K.-J., et al (2012). The lifespan of Korean eunuchs. Current Biology, *22(18), R792-R793. doi:10.1016/j.cub.2012.06.036
- Pérez-López, F. R., et al (2010). Gender differences in cardiovascular disease: hormonal and biochemical influences. Reproductive sciences (Thousand Oaks, Calif.), 17(6), 511-31. doi:10.1177/1933719110367829
- Kryspin-Exner, I., et al (2011). Geropsychology: the gender gap in human aging--a mini-review. Gerontology, 57(6), 539-48. doi:10.1159/000323154