Studies have found there are four or five women centenarians for every one man over 100. It must be in those two X chromosomes, right?
That’s what I thought until I picked up the May 2013 National Geographic, the one with the cute baby on the cover that announced, “This baby will live to be 120.” The article, On Beyond 100, didn’t explain the 120 years (I will attempt to do that in the future), but it did report on an interesting study from Italy.
It turns out Mussolini did more than just make the trains run on time. He continued a tradition that started after Italy’s chaotic unification in 1861. Each Italian township was required to record all births, marriages, and deaths. Records in Calabria began in 1866, and in 1994 researchers at the University of Calabria turned all 128 years into a cross-generational study. They compared the longevity of those with a parent or sibling who made it to at least 90, to those without long-lived relatives.
Sure enough, the study delivered strong evidence that genes play a big role in longevity; people with a parent or sibling who reached 90 were likely to live longer than the general population. But there was a surprise.
The genetic factors that lead to longevity appear to favor men over women.
So why do we see so many women outliving men? It may have to do with behavior. Are women more likely to seek medical care, eat well, and exercise? Do women, who are less likely to show off, drive fast, and fight, have fewer early deaths? Or is it something else? And why is the longevity gap between men and women closing?
Whatever it is, the Calabria study shows us that longevity is probably a mix of good genes, behavior, and environment, and it’s hard to sort it all out.
Gender and genetics only take you so far.
Even if we were to give longevity genes to everyone, there would still be people who lived shortened lives…by choice.