Midlife obesity linked to Alzheimer’s risk through brain inflammation

ST. LOUIS: New research highlights a troubling connection between obesity in midlife and an elevated risk of Alzheimer’s disease. Presented at the Radiological Society of North America’s Annual Meeting, the findings point to visceral fat—fat stored around abdominal organs—as a potential driver of brain inflammation and neurodegeneration.
The studies, conducted by scientists from the Mallinckrodt Institute of Radiology at Washington University in St. Louis, examined a small group of midlife adults with an average age of 50. They found that visceral fat played a significant role in the accumulation of amyloid proteins in the brain, which are closely linked to Alzheimer’s pathology. This protein build-up, often a precursor to cognitive decline, appears to be mediated more by visceral fat than by general obesity or other fat types like thigh or liver fat.
Further investigations revealed that visceral fat was also associated with decreased blood flow to critical brain regions, including the middle temporal cortex—a key area affected by Alzheimer’s. The researchers observed these changes independent of lifestyle adjustments like diet and physical activity, suggesting that visceral fat itself exerts a direct influence on brain health.
Dr. Mahsa Dolatshahi, a lead researcher, emphasized the role of visceral fat in systemic inflammation, a known contributor to Alzheimer’s disease. She pointed out that while early intervention strategies, such as diet and exercise, may help reduce body fat distribution, these effects are cumulative, and midlife presents a critical window for prevention.
The findings build on previous research linking visceral fat to amyloid protein accumulation up to 15 years before Alzheimer’s onset. However, none of the current studies have yet undergone peer review. Experts, including Dr. Verna Porter from the Pacific Neuroscience Institute, corroborated the results, noting that obesity and its metabolic effects, particularly visceral fat, increase inflammation, oxidative stress, and insulin resistance—all factors implicated in Alzheimer’s development.
Researchers plan to extend their studies to explore how genetic factors, social determinants of health, and longitudinal changes in fat distribution impact Alzheimer’s progression. While concrete evidence linking midlife obesity reduction to lower Alzheimer’s risk remains elusive, the growing body of research underscores the importance of addressing visceral fat early to safeguard long-term brain health.