Fat Distribution Found to Shape Brain Health Risks

A study published in Radiology, shows that the impact of obesity on brain health depends not just on body fat levels, but also on where fat is stored. Conducted by researchers at The Affiliated Hospital of Xuzhou Medical University in China, the analysis identified two previously undefined fat distribution types that appear most strongly linked to adverse cognitive and brain outcomes.

The study describes a “pancreatic predominant” profile, marked by unusually high concentrations of fat in the pancreas, and a “skinny fat” profile, in which individuals have elevated body fat despite not showing typical characteristics of obesity. These two fat distribution types were found to have the strongest associations with gray matter loss, faster brain aging, cognitive decline, and increased neurological disease risk.

“Our work leveraged MRI’s ability to quantify fat in various body compartments, especially internal organs, to create a classification system that’s data-driven instead of subjective,” explained study coauthor Kai Liu. “The data-driven classification unexpectedly discovered two previously undefined fat distribution types that deserve greater attention.”

To conduct the study, researchers analyzed MRI and clinical data from 25,997 participants in the UK Biobank, which includes physical measurements, lifestyle information, and imaging biomarkers. The researchers compared the identified fat distribution profiles with measures of brain structure and cognitive outcomes.

Individuals with the “pancreatic predominant” pattern had a proton density fat fraction in the pancreas averaging around 30 percent—two to three times higher than most other categories and up to six times higher than in lean individuals. Interestingly, this group also had high total body fat and body mass index but did not show similarly high liver fat levels. “In our daily radiology practice, we often diagnose ‘fatty liver,’” Dr. Liu said. “But from the perspectives of brain structure, cognitive impairment and neurological disease risk, increased pancreatic fat should be recognized as a potentially higher-risk imaging phenotype than fatty liver.”

The “skinny fat” type displayed high overall fat levels except in the liver and pancreas and was particularly associated with abdominal fat accumulation. “Brain health is not just a matter of how much fat you have, but also where it goes,” Dr. Liu said, highlighting how personalized assessment of fat distribution may guide new approaches to protecting cognitive health.