Groundbreaking study blows apart ‘I’m fat but fit’ claims

The possibility of being overweight but fit and healthy is often raised by people who say that they may be considered obese by technical definitions but can still run a marathons or undertake other fitness or health feat.

But a new study released by the University of Birmingham has brought those claims into serious question for the first time, with a finding that people who are obese and have no metabolic abnormalities are still at greater risk of heart disease, heart failure and stroke than those of normal weight with no abnormalities.

Rishi Caleyachetty, the lead author of the study. told Eureka Alert that previous studies of the issue had been limited, but that the university’s study was the largest of its kind, which allowed the researchers to work with people with a far greater array of body types, all of whom were “metabolically healthy “.

Metabolically healthy in this case meant that the people studied had no abnormalities such as diabetes, high blood pressure, or high cholesterol.

“Obese individuals with no metabolic risk factors are still at a higher risk of coronary heart disease, cerebrovascular disease, and heart failure than normal weight, metabolically healthy individuals,” Caleyachetty said of the study’s findings. “So-called ‘metabolically healthy’ obesity is clearly not a harmless condition and the term should no longer be used in order to prevent misleading individuals that obesity can be healthy.”

The researchers looked at the official health records of 3.5 million British adults who were all free from heart disease and fell into four body mass index categories: underweight, normal weight, overweight, and obese.It also classified the study participants depending on whether they were metabolically healthy or not.

The researchers followed up each individual about five years later, and found that the people who fell into the ‘metabolically healthy obese’ category had a 49 per cent higher risk of having developed heart disease over that five -year period, a 7 per cent higher risk of having had a stroke, and a 96 per cent higher risk of having suffered heart failure, compared to people who were in the ‘metabolically healthy normal weight’ category.

Krish Nirantharakumar, a senior author of the research, said that the research conclusion was that people on the obese weight range should be encouraged to lose weight, even if they were currently metabolically healthy. 

The University of Birmingham is ranked among the world’s top 100 universities. The groundbreaking research was funded by the university and has been published by the Journal of The American College of Cardiology.

Do you think it’s possible to be overweight or obese but fit and healthy?