Inflammation from belly fat may be linked to the early stages of Alzheimer’s disease decades before symptoms begin, new research has found.

“We’ve known for a while that as the belly size gets larger, the memory centers in the brain get smaller,” said Alzheimer’s disease researcher Dr. Richard Isaacson, a preventive neurologist at the Institute for Neurodegenerative Diseases of Florida.

“This study shows a brain imaging marker of neuroinflammation which I had not seen before,” said Isaacson, who was not involved in the new study. “The brain imaging links the belly fat, or visceral fat, to the brain dysfunction through an inflammatory cascade.”

The study found individuals in their 40s and 50s with a greater amount of hidden belly fat “had a higher amount of an abnormal protein called amyloid in a part of the brain that we know is one of the earliest places where Alzheimer’s occurs,” said senior author Dr. Cyrus Raji, associate professor of radiology at Washington University School of Medicine in St. Louis.