But the metabolic brain age was on average 3.8 years younger in women than in men.
"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, who is also an assistant professor of neurology and of neuroscience.
While age reduces the metabolism of all brains, women retain a higher rate throughout the lifespan, researchers reported Monday in the journal Proceedings of the National Academy of Sciences.
The US team looked at PET (Positron Emission Tomography) brain scan images from 205 men and women ranging in age from 20 to 82. In the main it confirms what would be expected - that the brain's metabolic age as indicated by how it uses glucose and oxygen is closely aligned with the chronological age of the person.
And while metabolic brain age might be useful to predict the risk of cognitive decline or identify factors that potentially could improve or worsen the trajectory of brain aging, the findings need to be validated in other cohorts, the researchers added.
"Ultimately, many studies keep showing that the differences between any two people tend to be negligible, and that the power of this type of study is in looking at large numbers of brain scans".More news: Jennifer Lawrence is engaged to art gallery director
To ensure their data was on point, the researchers also used the same algorithm but in reverse, feeding first the women's data and then applying it to the men's.
Researchers then tried using a female benchmark set with women's ages and brain metabolism.
"This vast amount of data" allowed the researchers "to convincingly show that, no matter how you look at it, males have more accelerated metabolic brain age (e.g., greater than their actual calendar age)", said Lockhart, who was not involved in the new study but who has researched the roles of vascular and metabolic disorders in the onset and progression of Alzheimer's disease.
They trained a machine-learning algorithm to find a relationship between people's age and their brain metabolism.
This can cause problems later in life and scientists hope to one day slow it down with state-of-the-art drugs or brain therapy.
Time wears differently on women's and men's brains.More news: Trump to meet with Kim Jong-un in Vietnam within weeks
"What this tells us is that sex has an effect on how the brain ages, metabolically speaking", he said. However the rates tend to be faster among men than women, they found.
This latest research now indicates that female brains, on average, appear to be about three years more youthful than the brains of males of the same age when it comes to brain metabolism.
As the researchers say, the extent of brain decline varies considerably between individuals. So they studied the brains of more than 200 adults. More brain sugar is devoted to aerobic glycolysis in children and young adults, but the fraction drops steadily with age, leveling off at very low amounts by the time people are in their 60s, Goyal and co-authors noted. Studies in rodents, meanwhile, suggested that estrogen could make the brain more adaptable to change.
"What we don't know is what it means", the lead author said.
In fact, brain metabolism might have little to do with diseases like Alzheimer's or dementia, said Dr. Gayatri Devi, a neurologist with Lenox Hill Hospital in New York City.More news: ALP forces suffer casualties in Taliban attack in Baghlan province