Brain scans show patterns of shrinkage. In areas involved in learning, memory and judgment. Experts hope that losing weight can reverse some of the damage.
Being overweight in midlife has been linked to an increased. Risk of developing Alzheimer’s disease or dementia. And a new study shows that brain changes in obese people mirror. some of those in those with Alzheimer’s disease.
Scientists at McGill University in Montreal analyzed brain scans of more. Than 1,300 people in the first study to directly. Compare brain shrinkage patterns in obese people. And Alzheimer’s patients.
The scans revealed similar brain thinning in both groups. In areas involved in learning, memory and judgment. According to a report published Tuesday in the Journal of Alzheimer’s Disease.
Obesity can cause changes in the body that increase the risk of Alzheimer’s. Including damage to blood vessels in the brain and the accumulation of abnormal proteins. Previous studies have found. New research takes this a step further.
“We showed that there is a similarity between the brains of people. who are obese and those who have Alzheimer’s,” said Philip Morris. a postdoctoral neuroscience researcher at McGill University and first author of the study. “And it boils down to the thickness of the cerebral cortex.”
The cerebral cortex, which handles the higher functions. Of the human brain such as speech, perception. Long-term memory and judgment, is the outermost layer of the brain.
Thinning in that brain region may reflect a decline in the number of brain cells, Morris said.
The McGill researchers suspect that obese people. And perhaps those who are overweight. with a BMI of 25 to 25.9 — may be able to slow cognitive decline if they can get closer to a healthy weight.
Morris was not able to identify a target weight. Why is obesity dangerous for the brain?
The science is not clear. Other conditions that are bad for the brain — including high blood pressure. high cholesterol and type 2 diabetes — are also linked to obesity, Morris notes.
To take a closer look at the effects of obesity on brain structure. Morris and his colleagues compared brain scans. from 341 Alzheimer’s patients and 341 obese individuals. with a BMI of 30 or greater, along with scans from 682 healthy individuals.
All brain scans and other data came from two large health. databases: the UK Biobank and the Alzheimer’s Disease Neuroimaging Initiative. a program recruiting participants across North America and funded in part. by the National Institutes of Health.
Metabolism researcher Sabrina Diano. director of the Institute of Human Nutrition at Columbia Irving Medical Center. said the new study “showed us something we didn’t know before.”
“Research has shown that normal areas of the brain. in obese people and those with Alzheimer’s disease are smaller in size. possibly due to a neurodegenerative process,” meaning. that nerve cells in these areas can suffer damage and die, Diano said.
The scans can’t show that obesity is thinning these areas. but it does suggest that controlling body weight may be a way to reduce risk, he said.
“We know that if you take a mouse that has a genetic predisposition to develop Alzheimer’s, and if you put that mouse. on a diet high in carbohydrates and fat—like the Western diet—you can induce the animal to gain body weight.
Can weight loss be reversed?
Dr. Assistant Professor of Neurology, Department of Cognitive Disorders, University of Pittsburgh. Joseph Malone said the study opens the door to further exploration. Of whether weight loss can cause certain changes in the brain.
“We know that obesity is associated with other diseases. that can affect blood vessels in the brain. Such as type 2 diabetes, high blood pressure, high cholesterol and inflammation. All which can cause blood vessels in the brain to collapse. And thus contribute to brain cell death,” Malone said.
Although the study did not show memory loss in obese people. It’s possible that what the researchers are seeing is an early stage. Of Alzheimer’s development, Malone suggested.
One limitation of the study is that it doesn’t directly report. What people are eating, just whether they are obese. Said Linda Van Horn. chief of nutrition at Northwestern University Feinberg School of Medicine.