A new study in the Journal of the American College of Cardiology found that 'healthy obese' adults had a higher prevalence of plaque build up in their arteries as compared to normal weight individuals.

There has been a lot of discussion in the last year about the concept of healthy obesity — that an individual who is clinically obese or overweight can be as healthy as individuals with a normal BMI. This specifically refers to people with an obese BMI who are metabolically healthy (normal blood pressure, cholesterol, and blood sugars). Some studies proposed that obesity can be a relatively benign condition. New research suggests that healthy obesity is a dangerous misnomer.

This newly published study examined 14,828 metabolically healthy Korean adults, ranging from 30-59 years of age. Participants with a body mass index (BMI) of greater than 25 were considered medically health obese (MHO)*. Results indicated that MHO participants had a higher level of coronary artery calcification (build up) than non obese participants. Researchers concluded that although there were not yet metabolic signs of heart disease in MHO patients, their weight was affecting their health.

Data also suggested that the idea of healthy obesity may be an artifact of how we define metabolic health. Obese individuals may be affected by metabolic factors below levels established as abnormal for normal weight individuals. In other words, normal lab values may be deceptive in obese individuals.

As with any journal article, it is important to recognize the flaws in the research study. The international generalizability of the study is greatly limited by the fact that the participants were all drawn from a single ethnic group. Researchers also assessed cardiovascular risk through CAC scoring – the use of this technique in low risk individuals is controversial. Many grains of salt involved in these findings.

That said, the results are consistent with large meta-analyses showing obese people to have a higher risk of death and cardiovascular disease when followed over time. The findings of several peer reviewed and large scale studies suggest that even in the absence of metabolic abnormalities, there are adverse effects of obesity - that the idea of healthy obesity is a myth that can lead both doctors and patients to assume good health when, in fact, medical complications are looming in the future.

* BMI is a flawed and outdated measurement. The inadequacies of the BMI scale should be a part of the discussion in any study that utilizes it. That said, its inadequacies don't discredit the study, but rather factor in to our discussion of it. Of relevance to this research, in the US, obesity is associated with a BMI of greater than 35 (25+ is considered overweight).