Excess upper-body fat seems to drive premature ageing while lower-body fat keeps women’s hearts younger, data from more than 21,000 UK Biobank participants show.
Summary
People with lots of upper-body fat tend to have prematurely aged hearts while women with more fat around the lower body have younger-looking hearts. The results come from an analysis of heart and body scans from more than 21,000 UK Biobank participants. Targeting specific fat deposits – for example, with medications such as Ozempic – could keep the heart healthy later in life.
People who have large amounts of fat hidden between their internal organs tend to have older-looking, more disease-prone hearts. Targeting this inter-organ fat – for example, with medications such as Ozempic – could slow down heart ageing and keep the organ healthy later in life.
And not all excess fat is harmful, scans from more than 21,000 UK Biobank participants revealed: women with more under-the-skin fat around the hips, thighs and buttocks tended to have hearts that appear younger and healthier.
A hidden driver of inflammation
We think of fat as just being an inert substance for storing energy, but it’s a really active, complex organ system.
Professor Declan O’Regan, Imperial College London, UK
“We think of fat as just being an inert substance for storing energy, but it’s a really active, complex organ system,” says study leader Declan O’Regan from Imperial College London, UK.
So-called visceral fat cushions and protects the upper-body organs, including the stomach, intestines, kidneys and liver. This type of fat doesn’t tend to be visible from the outside and the amount someone has doesn’t necessarily depend on their body weight.
Visceral fat produces substances that can trigger low-level inflammation across the whole body. Having a lot of visceral fat puts people at risk of health issues ranging from dementia to cancer. And it seems to drive premature ageing of the heart, O’Regan’s team discovered.
Heart-ageing sex differences
The study team calculated the heart age of 21,241 UK Biobank participants.
O’Regan’s team calculated 21,241 UK Biobank participants’ heart age, which depends on how the organ ranks across 126 factors – for example, its ability to fill with blood or heart-muscle scarring.
People who had more visceral fat tended to have a heart age older than their actual age. This link was particularly apparent for men, who also tended to have more visceral fat than women. Having a higher heart age also made people more prone to type 2 diabetes and heart-rhythm problems.
In contrast, fat under the skin around the hips, thighs and buttocks seems to protect women against ageing. Pre-menopausal women who had five kilograms of lower-body fat were, on average, nearly two-and-a-half years ‘heart-younger’.
The reason for this isn’t clear yet. It might be because this type of fat produces anti-inflammatory substances, or it could be linked to oestrogen. This hormone controls fat distribution and is known to be important for women’s cardiovascular health, O’Regan explains.
Targeting harmful fat
Anything that works to even slow down a little bit that rate of ageing could have quite a big effect on how long people stay healthy for.
Professor Declan O’Regan, Imperial College London, UK
The study is “a nice first demonstration that heart-age delta [the difference between heart age and real age] is a global proxy for cardiovascular health”, comments cardiovascular medicine researcher Steffen Petersen from Queen Mary University of London, UK. “Visceral adipose tissue, we all knew, is not good. What was not so clear is that there’s a difference between men and women, it seems, in terms of the fat distribution.”
Ways to reduce visceral fat and slow down heart ageing could include a balanced diet, physical activity and medications such as semaglutide (sold as Ozempic or Wegovy). Semaglutide is one of several drugs that mimic an appetite-regulating hormone. It might be able to specifically target visceral fat and “reprogram it, in some sense, so that it’s more benign”, O’Regan explains. A recent study with nearly 18,000 volunteers found that semaglutide protects from heart attacks and strokes – no matter whether people taking it lost weight or not.
“Aging is the biggest risk factor for cardiovascular disease,” O’Regan says. “Anything that works to even slow down a little bit that rate of ageing could have quite a big effect on how long people stay healthy for.”
Related publication
Related publication
- European Heart Journal, July 2025
