It’s a paradox that has baffled scientists for years, but a new study may shed light on why some people are ‘fat but fit .’
Researchers from the University of Leeds suggest that people who are overweight but have a seemingly healthy metabolism may have an especially good blood supply to their fat cells.
Dr Natalie Haywood, who led the study, said: “It’s a myth that you can be overweight and completely healthy – but there may be some truth to the ‘fat but fit’ paradox.
“People with better blood supply to their fat may be more metabolically healthy and could be protected against heart and circulatory diseases.”
In the study, the researchers studied a receptor called IGF1-R, which is known to play a role in the growth of new blood vessels.
The team removed this receptor in the cells lining the blood vessels of mice fed a high-fat diet, and found that new blood vessels grew into the fat.
Amazingly, this actually led to protection against heart and circulatory diseases in the long term.
While the reason for this remains unclear, the researchers suggest that blood vessels in fat may release bioactive chemicals which encourage fat cells to ‘brown.’
Brown fat burns calories to generate heat, helping to control blood sugar, blood pressure and cholesterol levels, according to the researchers.
The team now hopes to use these findings to help develop drugs that can copy this process, and protect against heart disease.
Dr Haywood added: “The next step is to identify the healthy bioactive signals released by blood vessels so that we can potentially harness them to combat heart and circulatory disease in obesity.”
However, experts have highlighted that people shouldn’t take the findings as an excuse to let their diets slide.
Professor Metin Avkiran, Associate Medical Director at the British Heart Foundation said: “Fat is an essential part of our diet, but too much of it can cause a wide range of health issues.
“This research may explain why some people who are overweight are more at risk of heart and circulatory disease than others. It’ll take a lot more research before we have a new drug to keep these fat cells healthy.
“For most people, with or without obesity, the best medicine will be a healthy diet and active lifestyle.”