Scientists found that healthy women have a “metabolic brain age” that is persistently younger than men’s of the same chronological age. This is evident from their early adulthood till their later life.
“Brain metabolism changes with age but what we noticed is that a good deal of the variation we see is down to sex differences,” said Marcus Raichle, a neurobiologist at Washington University school of medicine in St Louis. “If you look at how brain metabolism predicts a person’s age, women come out looking about four years younger than they are.”
Mani Goyal at the University’s Mallinckrodt Institute of Radiology, and lead author on the paper, said men’s brains were not ageing faster than women’s. “They start adulthood about three years older than women and that persists throughout life,” he said. “What we don’t know is what it means. I think this could mean that the reason women don’t experience as much cognitive decline in later years is because their brains are effectively younger.”
The study basing age on metabolism rather than birth date found an average 3.8 year difference between men and women. The discovery may help explain why women are more likely than men to stay mentally sharp in their later years.