The findings of the study, which was published in the journal Neurology on January 9, suggest that the combination of obesity and high waist-to-hip ratio could be a risk factor for brain shrinkage, which has been tied to elevated risk for memory decline and dementia. In hard numbers, 1,291 people who had a BMI of 30 or higher and a high waist-to-hip ratio had the lowest average gray matter volume, at 786 cubic centimeters; 514 people with a BMI of 30 or higher but without central obesity had an average gray matter volume of 793 cubic centimeters.
Gray matter contains most of your brain's 100 billion nerve cells, while white matter is filled with nerve fibers that connect the brain regions.
Brain shrinkage was less for people who were obese but did not have a high waist-to-hip ratio, suggesting both are important.More news: Netflix to track and stop users from sharing their accounts with friends
It was unclear whether obesity lead to brain structure abnormalities or the other way around, he said.
Experts think fat could trigger the immune system to overreact and damage the brain, causing it to shrink and raising the odds of obese people starting to lose their memories. "One particularly interesting finding is that, among individuals with obesity, those with greater waist to hip ratio (a marker of visceral fat around the abdomen), showed even lower gray matter volume", Bohon said.
Using a technique called magnetic resonance imaging, researchers studied the volumes of white and grey brain matter and volumes in various regions of the brain.
Dr Mark Hamer, who led the study from Loughborough University, said: 'Our research looked at a large group of people and found obesity, specifically around the middle, may be linked with brain shrinkage'.More news: Paris bakery blast causes multiple injuries
Links were also found between obesity and shrinkage in specific regions of the brain. "This will need further research, but it may be possible that someday regularly measuring BMI and waist-to-hip ratio may help determine brain health", he adds.
A limitation of the study is that people who agreed to take part in the study tended to be healthier than people who did not want to take part, so the results may not apply to the general population as a whole, the researchers noted. Follow Brain & Life® on Facebook, Twitter and Instagram. The AAN is dedicated to promoting the highest quality patient-centered neurologic care.
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