Hidden Abdominal Fat Linked to Arterial Damage, Study Finds

A recent study from McMaster University reveals that hidden fat stored deep within the abdomen and liver can significantly damage arteries, even in individuals who appear healthy. Published in the journal Communications Medicine on October 17, 2025, this research challenges the traditional use of body mass index (BMI) as a primary measure of obesity and sheds light on the role of visceral fat in heart disease.

The study highlights the dangers of visceral fat, which envelops internal organs, and hepatic fat, which accumulates in the liver. Both types of fat have been linked to increased risks of Type 2 diabetes, high blood pressure, and cardiovascular disease. However, until now, their specific impact on artery health had not been clearly understood. Researchers utilized advanced MRI imaging techniques and analyzed data from over 33,000 adults in Canada and the United Kingdom to uncover these links.

Using the data from two major cohorts, the Canadian Alliance for Healthy Hearts and Minds (CAHHM) and the UK Biobank, the research team found a strong correlation between visceral and hepatic fat and the thickening and narrowing of carotid arteries. These arteries are crucial as they supply blood to the brain, and their deterioration is a significant predictor of strokes and heart attacks.

Even after controlling for traditional cardiovascular risk factors like cholesterol and blood pressure, the study revealed that visceral and liver fat still played a substantial role in artery damage. Russell de Souza, co-lead author and associate professor at McMaster, emphasized the urgency of these findings, stating, “The findings are a wake-up call for clinicians and the public alike.”

Alongside de Souza, Marie Pigeyre, an associate professor in the Department of Medicine at McMaster, contributed to the study which demonstrated that visceral fat consistently correlated with carotid plaque buildup and artery wall thickening. Liver fat also showed a significant, albeit weaker, association.

The implications of this research extend beyond the academic realm. For clinicians, it suggests the necessity of moving beyond BMI and waist circumference measurements. Instead, they should consider imaging-based assessments of fat distribution to better evaluate cardiovascular risks.

As Sonia Anand, corresponding author of the study and a vascular medicine specialist at Hamilton Health Sciences, pointed out, “You can’t always tell by looking at someone whether they have visceral or liver fat. This kind of fat is metabolically active and dangerous; it’s linked to inflammation and artery damage even in people who aren’t visibly overweight.”

The study received support from various organizations, including the Canadian Partnership Against Cancer, the Heart and Stroke Foundation of Canada, and the Canadian Institutes of Health Research. Contributions also came from the Population Health Research Institute, Montreal Heart Institute, and Sunnybrook Health Sciences Centre. MRI reading costs were supported in-kind by Sunnybrook Hospital, and Bayer AG provided intravenous contrast materials.

This research brings to light the often-overlooked dangers of hidden fat and underscores the importance of rethinking obesity assessments. As the understanding of fat distribution and its implications for heart health evolves, so too must strategies for prevention and treatment.

For further details, refer to the study: de Souza, R.J., et al. (2025). “Visceral adipose tissue and hepatic fat as determinants of carotid atherosclerosis,” Communications Medicine, doi.org/10.1038/s43856-025-01123-y.