By Unlocking What’s Behind the Longevity Gap, Scientists Hope to Help Both Sexes Age Better

Women are living longer — but not healthier — than men

Many factors affect how long someone will live, including genetics, diet, lifestyle, socioeconomic status and environment. But, as highlighted in a recent article in The New York Times, one characteristic exerts even more influence on longevity: gender. Women might live longer, however, they aren’t living better. 

Scientists want to understand why. 

The longevity gap is a well-established phenomenon in which women outlive men by a number of years. But studies have found that women have shorter health spans (the number of healthy years a person lives), a gap that researchers are only beginning to understand. They hope that by discovering the reasons men and women age differently, they might be able to extend life and health spans for both genders.

The Longevity Gap

According to the Centers for Disease Control and Prevention, women have a life expectancy of around 80 years, while men live an average of 75 years. But women are generally more physically frail than men in old age, and more vulnerable to developing cardiovascular issues and Alzheimer’s disease after menopause. In a study analyzing data collected from all 183 of the countries that were part of the World Health Organization from 2000 to 2019, American women had a health span-lifespan gap of 13.73 years, which is 2.65 years longer than the gap men experience. This study further supports the statistics that show women spend a greater portion of their lives in ill health than men do.

Dr. Dena Dubal, a professor of neurology at the University of California, San Francisco, told the Times, “If we can understand what makes one sex more resilient or vulnerable, then we have new pathways, new molecular understanding, for new therapeutics that could help one or both sexes also be resilient.” 

What Scientists Already Know

A growing body of research, including a study of multiple species, suggests that the XX set of female sex chromosomes may affect longevity. And in a 2018 study conducted by Dubal’s lab, scientists looked at genetically manipulated mice with different combinations of sex chromosomes and reproductive organs. Those with two X chromosomes and ovaries lived the longest, followed by mice with two X chromosomes and testes. Mice with XY chromosomes had shorter lifespans. 

“There was something about the second X chromosome that was protecting the mice from dying earlier in life, even if they had testes,” Dubal told the Times. “What if there was something on that second X chromosome that was in some ways a sprinkle of the fountain of youth?”

And sex hormones like estrogen also play a huge role in longevity, research suggests. Studies have shown that the female immune system is bolstered by estrogen, allowing women to produce or mount greater immune responses compared to men. One 2017 analysis showed that women who experienced menopause later in life lived longer than those who experienced it earlier, thanks to their extended time with higher levels of estrogen bolstering their immune function. 

American women experience a healthspan/lifespan gap of over 13 years

Why More Studies Are Needed

This field of study is particularly challenging because there are so many other variables researchers need to account for, including genetics, behaviors and external factors like war or gun violence — all contributing factors to the differences between men’s and women’s health  and lifespans. 

Researchers have just begun to scratch the surface in terms of narrowing down likely influences in each category of variables separately. Meanwhile, it’s up to people to take those steps they can take to keep themselves healthier, longer.