A long-term MRI-based study has revealed that lower accumulation of visceral abdominal fat significantly slows brain aging, preserves critical brain structures, and improves cognitive performance in late midlife. Importantly, researchers found that these benefits occur independently of overall weight loss.
The findings, published in Nature Communications, suggest that glucose control and improved insulin sensitivity play a central role in protecting the brain from age-related degeneration.
Notably, the study is the first to connect repeated MRI-based measurements of cumulative visceral fat with long-term changes in brain structure and cognitive function.
Researchers Conducted a Long-Term MRI-Based Investigation
The research team followed 533 women and men in late midlife for a period ranging from 5 to 16 years. Participants had previously enrolled in four major long-term controlled dietary clinical trials—DIRECT, CASCADE, CENTRAL, and DIRECT-PLUS.
Researchers from Ben-Gurion University of the Negev led the study in collaboration with scientists from Harvard University, Leipzig University, and Tulane University.
Throughout the follow-up period, the team repeatedly assessed visceral fat and brain structures using advanced MRI imaging. In addition, they evaluated cognitive performance through the Montreal Cognitive Assessment (MoCA) test.
Lower Visceral Fat Preserved Brain Structure and Cognitive Function
The study demonstrated that participants who accumulated less visceral fat over time maintained better cognitive performance and healthier brain structures.
Specifically, researchers observed:
- Higher MoCA cognitive scores
- Better preservation of total brain volume
- Greater gray matter volume retention
- Improved Hippocampal Occupancy Score, a key indicator of memory and brain aging
- Slower enlargement of brain ventricles, a recognized marker of brain atrophy
Furthermore, researchers found that persistently high visceral fat levels accelerated brain volume loss, particularly in the hippocampus, a region essential for memory and learning.
Visceral Fat Emerged as the Key Risk Factor
Importantly, the study showed that visceral fat—not overall body weight or BMI—drove the association with brain aging.
Researchers did not observe similar effects with subcutaneous fat, whether superficial or deep. Likewise, body mass index failed to predict brain degeneration in the same way.
Moreover, participants who reduced visceral fat during an 18-month dietary intervention showed better preservation of brain structures even 5 to 10 years later. These findings remained significant after adjusting for total weight loss and other contributing factors.
As a result, the researchers concluded that reducing abdominal visceral fat itself—not simply losing weight—offers long-term benefits for brain health.
Glucose Control May Explain the Brain-Protective Effect
As reported by medicalxpress, the study further identified glucose regulation as the primary pathway connecting visceral fat and brain aging.
Researchers found that fasting glucose and HbA1c levels consistently predicted structural brain changes over time. In contrast, blood lipid levels and inflammatory markers showed no comparable association.
These findings support the theory that insulin resistance and chronic glucose imbalance may:
- Impair blood flow to the brain
- Damage the blood-brain barrier
- Accelerate degeneration of gray matter and the hippocampus
Consequently, maintaining healthy glucose metabolism may help protect against cognitive decline and neurodegeneration.
Experts Highlight the Importance of Targeting Visceral Fat
Prof. Iris Shai, who led the study, emphasized the practical implications of the findings.
“The findings point to glucose control and reduction of visceral abdominal fat as measurable, modifiable, and achievable targets in midlife—with real potential to slow brain degeneration and reduce the risk of cognitive decline,” she said.
Dr. Dafna Pachter, the study’s first author, also stressed that body weight alone does not adequately reflect metabolic health.
“Weight alone is not a sensitive marker of the profound metabolic changes occurring in the body. We found that even when weight loss is modest, sustained reductions in visceral fat are associated with preservation of brain structure and a slower rate of atrophy,” she explained.
Findings Could Transform Prevention Strategies
This study represents the largest and longest investigation to date examining the relationship between cumulative visceral fat exposure and brain aging through repeated MRI assessments.
By integrating long-term measurements of abdominal fat, brain structure, and cognition, researchers successfully identified visceral fat as a specific and modifiable metabolic risk factor for brain aging.
Consequently, the findings could reshape preventive strategies for cognitive decline by shifting the focus from general obesity to targeted reduction of harmful abdominal fat and improved glucose control.