Researchers aimed to uncover an answer for the pressing question, Why do those who are overweight or obese outlive their normal weight counterparts? Furthermore, would this obesity paradox work in all circumstances? The researchers found obesity does not offer protection against all condition, especially cardiovascular disease.
Samuel Preston, Ph.D., from the University of Pennsylvania said, “There are claims that … it’s good to be obese when you have cardiovascular disease, that if you have fat stores, maybe you’ll live longer. It’s conceivable that there are health advantages. But we show they are overwhelmed by the disadvantages of being obese, once you control for these two sources of bias.”
Preston, along with Andrew Stokes, Ph.D., from the University of Boston, examined data from over 30,400 obese participants – 3,388 had cardiovascular disease.
Weight history was included in the research. According to Stokes, excluding it, “would be like classifying a lifelong smoker who quit the day before the survey as a non-smoker, even though we know that if you’re a lifelong smoker you carry those risks over even if you stop smoking.” The addition of weight history “turns out to have a profound effect on the findings,” Stokes said. This eliminated a mortality advantage in overweight and obese people.
Smoking was also included, which further resolved the paradox. Smokers are less likely to be obese and obese individuals are less likely to smoke.
The obesity paradox vanished after weight history was accounted for. The researchers believe their findings could improve treatment for obese patients with cardiovascular disease as some clinicians may consider the fat paradox.
Preston added, “There’s every reason to imagine that clinicians are at least confused, and in some cases, are believing that being overweight or obese is a good thing among people with cardiovascular disease, diabetes and other conditions for which a paradox has been demonstrated.”
Stokes concluded, “This may be trickling down into clinical decision making, which is concerning because we don’t think it’s a real finding.”