Too much visceral fat—the kind that collects deep in your midsection and wraps around your organs—may accelerate aging in your heart and blood vessels, a new study shows.
Visceral fat is sneaky: You can carry a lot of it without knowing—and still fall within a “healthy” weight range if you do. But it’s more harmful than fat found directly under the skin—known as belly fat or subcutaneous fat, Declan O’Regan, MBBS, PhD, lead researcher and a professor at the MRC Laboratory of Medical Sciences and Imperial College London, told Health.
Visceral fat has been linked to diabetes, cardiovascular disease, and other chronic conditions.
But the new study, published Aug. 22 in the European Heart Journal, is the first to suggest that it may also speed up aging, O’Regan said.
The study underscores that “individuals should pay attention to their total body fat but also to its distribution,” said Nour Makarem, PhD, an assistant professor of epidemiology at the Columbia University Mailman School of Public Health, who reviewed the new study.
The team evaluated imaging scans from 21,241 participants in the UK Biobank, a comprehensive health database. The scans revealed details about their hearts, blood vessels, and distribution of both visceral and subcutaneous fat.
Using artificial intelligence, the researchers identified signs of organ aging, such as stiff and inflamed tissues, and assigned each participant a heart age.
People whose heart age exceeded their chronological one generally had higher levels of visceral fat.
Visceral fat increases inflammation, which likely contributes to faster aging, O’Regan said.
It also promotes insulin resistance, an early step in the development of diabetes and heart disease, and increases “bad” cholesterol, making it more likely to accumulate in blood vessels and lead to cardiovascular disease, added Tiffany Powell-Wiley, MD, MPH, a senior investigator with the National Institutes of Health who has studied visceral fat and cardiovascular risk but wasn’t involved in the new study.
On the flip side, O’Regan said, physically fit people with obesity had a ‘younger’ cardiovascular age than unfit people.
That may be because exercise helps reduce visceral fat. A 2024 study found that regular exercisers were more likely to store fat in subcutaneous tissue rather than as visceral fat, and the visceral fat they did have was less harmful—even if they were considered overweight or obese.
The researchers also discovered notable differences between the sexes when it came to fat and heart aging.
Fat around the belly—or being “apple” shaped—was predictive of early cardiovascular aging in men. Interestingly, fat around the hips and thighs, also known as “pear” shaped, appeared to be protective against heart aging in women. (In these regions, fat may release chemicals that block inflammation, O’Regan said.)
Women also tended to have more subcutaneous fat, while men were prone to high levels of visceral fat—and it increased more sharply with age, rising by about 8.2% per decade, compared to 5.3% in females. Hormone differences may help explain this, research has found.
The team also revealed a link between higher estrogen levels in premenopausal women and slower heart aging, suggesting the hormone may play a protective role.
While body mass index (BMI) has long been used to determine obesity—and predict related health risks—the researchers found that unlike fat distribution, the metric wasn’t linked to heart aging. As such, fat distribution is a more important factor to consider, said O’Regan.
“It’s important to know where fat is stored to know its potential harm,” O’Regan said.
The challenge is that it’s hard to know how much visceral fat you actually have.
Currently, the only reliable way to measure it is through an MRI or Dual-Energy X-ray Absorptiometry (DEXA) scan—tests that aren’t typically performed or covered by insurance, Carl Lavie, MD, the medical director of cardiac rehabilitation and preventive cardiology at the John Ochsner Heart and Vascular Institute in New Orleans, told Health.
A more affordable way to estimate visceral fat, Lavie added, is to measure your waist circumference and test your triglyceride levels.
While following a healthy diet is always beneficial, research is mixed on whether diet alone can significantly reduce visceral fat. A 2023 study, for example, found that simply cutting calories had little effect. Meanwhile, another paper found that a low-carb diet and intermittent fasting led to weight loss—with the fasting showing the greatest impact.
What matters most, according to Lavie, is getting enough exercise. A 2022 study identified the most effective strategy: a combination of high-intensity interval training—or HIIT—and aerobic exercise.
