
Women, on average, live longer than men. This trend can be seen as far back as records stretch, and is true of every country in the world today. Many explanations have been put forward: men take more risks or smoke more, oestrogen is protective against health conditions, two X chromosomes are better than one… the list goes on. Some of these can account for small fractions of the difference; many have been debunked. None are wholly satisfying.
Now, researchers have come up with an intriguing alternative explanation for much of this lifespan difference – that it all comes down to the Y chromosome. Specifically, the idea is that as men grow older, they lose this chromosome from many of their cells, which drives age-related disease.
Losing your Y chromosome in this way isn’t something that you would notice happening. “As far as I know, there are no data to suggest that men with loss of Y would feel it,” says Lars Forsberg at Uppsala University in Sweden. However, it turns out that a significant fraction of older men are affected, and researchers are now uncovering long-term consequences for the immune system and the risk of developing cancer, heart disease and even Alzheimer’s.
“If you’re a male, you do not want to lose your Y chromosome, it’s definitely going to shorten your life,” says Kenneth Walsh at the University of Virginia. The growing recognition of the importance of the Y chromosome for general health is opening the door to potential new ways to keep men healthier as they age.
Most people…