Excess fat surrounding the abdominal organs – known as visceral fat – during middle age may increase the risk of developing Alzheimer’s later in life, new research has revealed that has linked this type of hidden fat to changes that are They would occur in the brain for up to 15 years before the first symptoms of this dementia begin to appear.
To reach this conclusion, the researchers compared the brain MRIs of 54 people between 40 and 60 years old with an average age of 50 years and an average body mass index (BMI) of 32, with their levels of abdominal fat, BMI, obesity and insulin resistance. The goal of the MRIs was to determine the brain size of these individuals, as well as the levels of beta amyloid and tau proteins that have been linked to Alzheimer’s. The study’s findings will be presented at next week’s annual meeting of the Radiological Society of North America (RSNA), and are considered preliminary until published in a peer-reviewed scientific journal.
“Although there have been other studies linking BMI with brain atrophy, or even an increased risk of dementia, no previous study has linked a specific type of fat to the Alzheimer’s disease protein in cognitively normal people,” the study said. researcher Dr. Mahsa Dolatshahi, postdoctoral research fellow at the Mallinckrodt Institute of Radiology at Washington University School of Medicine in St. Louis in a news release.
Reduce visceral fat to prevent Alzheimer’s
Dolatshahi has also explained that other similar studies have not investigated the differential role of visceral and subcutaneous fat – especially in reference to the amyloid pathology associated with Alzheimer’s – during middle age, a stage in which people who will later develop the disease have not yet shown signs of cognitive decline.
The researchers found that people who had more visceral fat compared to the fat found just under their skin tended to have higher levels of amyloid in the precuneus cortex, an area of the brain known to be affected by amyloid pathology. in the early stages of Alzheimer’s disease.
“Inflammatory secretions from visceral fat can lead to inflammation in the brain, one of the main mechanisms contributing to Alzheimer’s disease.”
They observed that this relationship was worse in men than in women and that higher measurements of visceral fat were also related to increased inflammation in the brain. There are several pathways that may play a role, Dolatshahi said. “The inflammatory secretions of visceral fat, as opposed to the potentially protective effects of subcutaneous fat, may lead to inflammation in the brain, one of the main mechanisms contributing to Alzheimer’s disease.”
These findings could help doctors diagnose and treat people at risk of developing Alzheimer’s, said lead researcher Dr. Cyrus Raji, director of neuromagnetic resonance imaging at the Mallinckrodt Institute of Radiology. “This study highlights a key mechanism by which hidden fat may increase the risk of Alzheimer’s disease,” Raji said.
“It shows that such brain changes occur as early as age 50, on average, up to 15 years before the first symptoms of Alzheimer’s memory loss occur.” By reducing a person’s amount of visceral fat, doctors may be able to reduce future brain inflammation and prevent dementia or Alzheimer’s, Raji said.
“By going beyond body mass index to better characterize the anatomical distribution of body fat on MRI, we now have a unique and better understanding of why this factor may increase the risk of Alzheimer’s disease,” Raji concludes.
