People Can Be Obese But Healthy
What about people who are obese but healthy?
June 27, 2013
The American Medical Association should have heeded the recommendation of its own Council on Science and Public Health to not classify obesity as a disease. This classification makes no empirical sense, as there are plenty of people in the obese category who are perfectly healthy.
I am not denying that there are some health risks associated with having an elevated Body Mass Index. Notably, a higher BMI is associated with a greater risk of cardiometabolic abnormalities, as measured by blood pressure, triglycerides, cholesterol, glucose, insulin resistance and inflammation. Still, more than half of "overweight" and almost one-third of "obese" people have normal profiles, according to a 2008 study. Moreover, almost one quarter of "normal weight" people have metabolic abnormalities.
Treating obesity as a disease thus implies the overtreatment of 20 million obese (or 56 million overweight and obese) Americans who have no metabolic abnormalities and the undertreatment of 16 million "normal weight" Americans who have such abnormalities.
Some argue that the problem lies with BMI as a measure, which does not distinguish between fat, muscle or bone. As flawed as BMI is as a measure, however, it is not clear that there are better ones. A 2009 study estimated excess deaths for standard BMI levels as well as for comparable levels of percentage body fat, waist circumference, hip and arm circumferences, waist:hip ratio, the sum of four skinfold thicknesses and waist:stature ratio. It found no systematic differences between BMI and other variables.
In other words, it is not just that BMI is a poor measure of obesity but that obesity is a poor predictor of health.
Several studies have shown that physically fit "obese" individuals have lower incidence of heart disease and mortality from all causes than do sedentary people of "normal" weight. A recent clinical trial published in the New England Journal of Medicine showed that adopting a Mediterranean diet reduced cardiovascular risk independent of weight loss.
If the AMA's goal is to address the serious diseases of type 2 diabetes and heart disease, it would be more productive and accurate for the association to urge doctors to focus on cardiometabolic risk, recognizing that there are both metabolically-healthy and metabolically-unhealthy individuals in all categories of weight. Rather than promote weight loss per se, doctors should instead encourage their patients of all sizes to incorporate physical activity and a balanced diet into their lives.