A new study links visceral fat, a deep layer of abdominal fat, to increased brain amyloid and tau proteins—key markers of Alzheimer’s disease—decades before dementia symptoms arise. Researchers found that visceral fat accounted for 77% of the relationship between high BMI and amyloid accumulation, while other fat types showed no similar impact. The study highlights how managing visceral fat through lifestyle changes or medication could reduce Alzheimer's risk.