A recent study by Washington University School of Medicine in St. Louis has revealed why women can stay mentally sharp longer than men. Manu Goyal, an MD who is also an assistant professor of neurology and of neuroscience, and his colleagues have found that women's brains appear to be three years younger than men's of the same age.
As many as 121 women and 84 men ranging in age from 20 to 82 years participated in the research. They underwent PET scans to measure the flow of oxygen and glucose in their brains. Like other organs in the body, the brain uses sugar as fuel. But how it metabolizes glucose can reveal a lot about the brain's metabolic age. So Goyal and his colleagues, including Marcus Raichle, MD, the Alan A. and Edith L. Wolff Distinguished Professor of Medicine and a professor of radiology, and Andrei Vlassenko, MD, Ph.D., an associate professor of radiology, studied 205 people to figure out how their brains use sugar.
A machine-learned algorithm showed that women's brains were on average about 3.8 years younger than their chronological ages. They also performed the analysis in reverse. When compared to men, male brains were about 2.4 years older than their true ages
"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," Goyal said. He noted that the difference between men and women's brain ages was relatively small compared with other well-known sex differences, such as height.
The relative youthfulness of women's brains was detectable even among the youngest participants, who were in their 20s. "It's not that men's brains age faster -- they start adulthood about three years older than women, and that persists throughout life," said Goyal.
But why do women have better cognitive abilities?
Goyal 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.”
Sonakshi Goel is an intern with SheThePeople.TV