Yet Another Theory on the Human Gender Gap in Longevity

Women have a longer life expectancy than men, but why is this? There is no definitive answer to that question, but many competing theories exist. It is a good illustration of the point that the biochemistry of aging is, in detail, enormously complex and still poorly understood as a process with definitive causes and consequences at each stage and in each tissue type. There is a mountain of data, but many more mountains to be cataloged yet, and linking together what is known into a coherent picture is another massive task still in the comparatively early stages. In the research noted here, the authors advance a novel theory on the gender longevity gap, painting the comparative longevity of women as a modern phenomenon driven by a combination of improved medical technology and cardiovascular disease rates.

With regards to the complexity of aging, it is fortunately the case that we don't need a full understanding of the progression of aging if researchers just focused on repairing what we know to be the root cause cell and tissue damage. The situation is akin to that of rust in an ornate metal structure: there is a big difference in effort between (a) just rust-proofing the thing and (b) building a complete module of how rust works and interacts at the molecular level and how exactly, in detail, that causes various structural failure modes over decades of exposure to the elements. In aging research, there is a lot more work on (b) than on (a), which is fine from the pure science perspective where the only goal is complete understanding, but not so good from the point of view of producing therapies for aging in time for you and I to benefit.

Across the entire world, women can expect to live longer than men. But why does this occur and was this always the case? According to a new study, significant differences in life expectancies between the sexes first emerged as recently as the turn of the 20th century. As infectious disease prevention, improved diets and other positive health behaviors were adopted by people born during the 1800s and early 1900s, death rates plummeted, but women began reaping the longevity benefits at a much faster rate. In the wake of this massive but uneven decrease in mortality, a review of global data points to heart disease as the culprit behind most of the excess deaths documented in adult men. "We were surprised at how the divergence in mortality between men and women, which originated as early as 1870, was concentrated in the 50-to-70 age range and faded out sharply after age 80."

Focusing on mortality in adults over the age of 40, the team found that in individuals born after 1880, female death rates decreased 70 percent faster than those of males. Even when the researchers controlled for smoking-related illnesses, cardiovascular disease appeared to still be the cause of the vast majority of excess deaths in adult men over 40 for the same time period. Surprisingly, smoking accounted for only 30 percent of the difference in mortality between the sexes after 1890. The uneven impact of cardiovascular illness-related deaths on men, especially during middle and early older age, raises the question of whether men and women face different heart disease risks due to inherent biological risks and/or protective factors at different points in their lives.

Link: https://news.usc.edu/83648/why-dont-men-live-as-long-as-women/