Visceral Fat Linked to Alzheimer’s Risk: A Preventive Insight

At this year’s annual meeting of the Radiological Society of North America, a remarkable study has shed light on the intricate relationship between body fat and Alzheimer’s disease, a connection that could hold the key to preventing this devastating illness.

Researchers have identified a specific type of fat in the body—visceral fat—as a harbinger of amyloid and tau protein markers linked to Alzheimer’s. These markers can be detected up to two decades before the onset of any dementia symptoms, highlighting a critical window for possible intervention.

Research Insights

The lead researcher, Dr. Mahsa Dolatshahi, a post-doctoral research associate at the Mallinckrodt Institute of Radiology at Washington University School of Medicine, emphasized the potential for lifestyle changes to mitigate the impact of this type of fat.

Weight loss and reduction of visceral fat may be crucial steps toward delaying or even preventing the progression of Alzheimer’s disease, a thought-provoking prospect in a world where around 6.9 million Americans aged 65 and older are currently grappling with this condition—numbers that could escalate to 13 million by 2050 without significant medical advancements.

The study intricately examined the interplay between modifiable lifestyle factors like obesity, fat distribution, and metabolic health concerning Alzheimer’s pathology.

Researchers worked with a diverse group of 80 people in midlife, predominantly in their late 40s, with 57.5 percent classified as obese.

The implications of their findings could be profound, as participants underwent brain PET scans, body MRIs, and metabolic evaluations, including crucial measurements of glucose, insulin, and lipid profiles.

Methodology and Results

Dr. Dolatshahi described the research methodology, which involved a deep dive into metrics such as body mass index, visceral and subcutaneous fat, and liver fat fraction, correlating these measures with amyloid and tau deposition in the brain.

PET scans employing specialized tracers illuminated the presence of amyloid plaques and tau tangles characteristic of early Alzheimer’s pathology.

The results were striking: a pronounced correlation emerged between high levels of visceral fat and an increased concentration of amyloid in the brain, with visceral fat accounting for an astounding 77 percent of the impact of elevated BMI on amyloid accumulation.

Notably, other types of fat did not contribute similarly to the rise in Alzheimer’s-related pathology observed in those classified as obese.

Further analysis revealed a compelling connection with metabolic health—greater insulin resistance and lower HDL levels corresponded with higher amyloid concentrations, suggesting that people with elevated HDL levels experienced a mitigation of the negative effects of visceral fat on amyloid pathology.

Future Directions

The findings underscore a pressing need to address metabolic health alongside obesity in strategies aimed at managing Alzheimer’s disease risk.

This research stands out in its pioneering focus on the specific roles of visceral and subcutaneous fat, effectively linking metabolic profiling to the overarching narrative of Alzheimer’s amyloid pathology during midlife.

Looking ahead, Dr. Raji, along with Dr. Dolatshahi and their team, plans to present further research at RSNA 2024, exploring how obesity and visceral fat influence cerebral blood flow in cognitively healthy midlife adults.

Preliminary findings suggest that high visceral fat is associated with decreased overall brain blood flow—a relationship not observed in those with varying levels of subcutaneous fat.

The implications of these insights are far-reaching, especially in a society where nearly three-quarters of people are classified as overweight or obese.

Understanding the detrimental effects of visceral obesity on brain health paves the way for targeted lifestyle changes and potentially effective weight-loss interventions that could enhance cerebral blood flow and reduce the risk of Alzheimer’s disease.

As the research unfolds, it holds out hope for a future where proactive measures may alter the trajectory of cognitive health in America and beyond.

Study Details:

• Title: Hidden fat predicts Alzheimer’s 20 years ahead of symptoms
• Authors: Mahsa Dolatshahi, Cyrus A. Raji, et al.
• Publication Date: December 2, 2024
• Link: https://press.rsna.org/timssnet/media/pressreleases/14_pr_target.cfm?ID=2541