A doctor and a professor discuss – Are there health benefits to being overweight?
Carl J. Lavie:
The good news for those who may be struggling to lose weight and keep it off is this: As I explored in my book “The Obesity Paradox,” there can be surprising benefits to carrying around a few extra pounds. In fact, being out of physical shape and having low overall fitness is actually a far greater danger to health than fat, especially in people who are only slightly overweight.
Using information on weight history, it is possible to address this seemingly intractable source of bias. Weight history makes it possible to distinguish people who were slim throughout their lives from those who were formerly overweight or obese but lost weight.
In other words, Stokes is claiming that most studies include weight at the start of the study and throughout the study, but neglect the weight history of the person. The formerly overweight/obese who were ‘normal’ weight at the time of the study may have higher mortality due to issues related to the former excess weight, and therefore skew the results to look like overweight people have lower mortality (as a group). Interesting.
The study by Stokes and Preston goes into further depth on the weight history theory. The conclusions are stark (emphasis mine) :
Our results suggest the burden of overweight and obesity on mortality is likely substantially larger than commonly appreciated. If correct, this may have serious implications for the future of life expectancy in the United States. Although the prevalence of obesity may level off or even decline, the history of rapidly rising obesity in the last 3 decades cannot be readily erased (63). Successive birth cohorts embody heavier and heavier obesity histories, regardless of current levels. Those histories are likely to exert upward pressure on US mortality levels for many years to come.