The Nov. 7, 2007, issue of the Journal of the American Medical Association published an article that stoked the continuing controversy about the relationship between weight and mortality. The authors from the Centers of Disease Control (CDC) initially had published an article in the same journal in 2005 indicating that overweight (BMI 25 to 30) individuals had a decreased overall mortality compared to normal-weight (BMI 18.5 to 25) individuals.
These results were immediately met with cries of foul play from the medical establishment, led by Harvard Medical School. After all, if overweight individuals were actually living longer, then the growing concern (and funding) for obesity research would be significantly impacted. So in this new article two years later, the authors from the CDC published an even more detailed analysis with even more recent data on mortality from different diseases. The results were the same.
Overweight people are less likely to die from any cause of death that is not related to heart disease or cancer than normal weight individuals. And even the deaths from heart disease and cancer were no greater than normal weight individuals. Even when you include obese (BMI 30-35) with the overweight individuals, the overall mortality was less than normal-weight individuals. Yes, if people are severely obese (BMI greater than 35), then the chances of dying are greater, but this accounts for a very small proportion of the population.
The response from Harvard on this new study was “it’s ridiculous.” Now there’s a rational scientific reply. My response is that the seemingly paradoxical results can be easily explained once you take into account the levels of silent inflammation. If you are normal weight and inflamed, then you are probably going to die at an earlier age. If you are overweight or obese and not inflamed, you are going to live longer. Of course, if you are overweight or obese and also inflamed, you are going to be in a boatload of trouble.
The real answer is to reduce inflammation first; then worry about reducing weight.