[The Biological and Behavioral Foundations of the Longevity Gap Between Men and Women]-[Why do women live longer than men?]

The Global Longevity Disparity

Statistical data consistently reveals a significant gap in life expectancy between genders. According to the Office of National Statistics, between 2018 and 2020, women in the UK had a life expectancy of 82.9 years, compared to only 79 years for men. This is not an isolated phenomenon; it is a "common trend across various countries" and is even observed in other mammal species, such as great apes. The question of why this discrepancy persists has long intrigued the scientific community, leading to investigations into both behavioral and biological determinants.

The Role of Behavioral Risk-Taking

Dr. Paminder Sashtev, a professor of neuropsychiatry, points to behavioral factors as a major contributor to the shorter lifespans of men. He suggests that men are "more likely to take life-threatening risks," such as engaging in physical fights or participating in high-speed driving that leads to fatal car accidents. Furthermore, men are statistically more prone to "unhealthy habits like smoking or drinking excessively." These lifestyle choices have "life-shortening consequences in the long term," creating a behavioral foundation for the longevity gap.

Testosterone and the Biological Cost

Beyond lifestyle, biological differences—specifically hormonal profiles—play a critical role. Research indicates that testosterone, the primary male hormone, is closely linked with the "risk-taking" behaviors mentioned earlier. Consequently, men who produce "abundant testosterone" may face a reduced life expectancy.

Kyung Jin Min, a professor of biological sciences, further explains that male sex hormones can "diminish immune function" and increase the susceptibility to cardiovascular diseases. A compelling piece of evidence comes from a study of Korean eunuchs. By examining the health records of 81 men who were castrated in childhood, researchers discovered that these individuals lived "14 to 19 years longer than their non-castrated counterparts." This suggests that testosterone may "impede the release of certain cells" that are vital for the body's defense against diseases, thereby shortening the male lifespan.

The Protective Nature of Oestrogen

In contrast to the risks associated with testosterone, female sex hormones offer distinct advantages. Oestrogen, the primary female sex hormone, is widely considered to have "protective properties." A 2013 study published in the Journal of Endocrinology highlights that these hormones contribute to longevity by "preserving DNA" through the maintenance of healthy cells. By "preventing damage that could lead to diseases," oestrogen acts as a biological shield, further widening the gap between male and female longevity.

Conclusion

In summary, the disparity in life expectancy is not the result of a single factor but a complex interplay between behavior and biology. While male longevity is often hindered by a propensity for high-risk behaviors and the physiological toll of testosterone on the immune system, women benefit from the protective, restorative effects of oestrogen. Understanding these mechanisms provides a clearer picture of why these trends persist across human and animal populations alike.