Women’s brains are, on average, around four years younger than men’s, research finds.
It could help explain why women tend to stay sharper with age than men.
Older women typically score better on tests of memory, reasoning and problem solving than older men.
Dr Manu Goyal, the study’s first author, said:
“We’re just starting to understand how various sex-related factors might affect the trajectory of brain aging and how that might influence the vulnerability of the brain to neurodegenerative diseases.
Brain metabolism might help us understand some of the differences we see between men and women as they age.”
For the study, 205 people had scans to examine how their brains were processing oxygen and sugar.
Typically, as people age, less sugar is used for sustaining brain development and maturation.
The results showed that, metabolically, men’s brains were 2.4 years older than their chronological age.
Women’s brains, though, were 3.8 years younger.
Dr Goyal said:
“The average difference in calculated brain age between men and women is significant and reproducible, but it is only a fraction of the difference between any two individuals.
It is stronger than many sex differences that have been reported, but it’s nowhere near as big a difference as some sex differences, such as height.”
The additional youthfulness of women’s brains was even measurable among those in their 20s.
Dr Goyal explained:
“It’s not that men’s brains age faster — they start adulthood about three years older than women, and that persists throughout life.
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, and we’re currently working on a study to confirm that.”
The study was published in the journal Proceedings of the National Academy of Sciences (Goyal et al., 2019).