You can make comparisons to climate denial, but I really don’t think causal relationships have been established. To me it seems much more likely that there are factors which tend to cause both obesity and obesity-linked diseases so obesity is merely a proxy. It is recognized that while the general population is less healthy when they are obese, there are subgroups of the population who are more healthy when they are obese. And then we use BMI as a poor metric of a poor proxy for health.
Here’s the thing: “Obese” means BMI 30 or higher. “Overweight” means BMI 25-30. Studies conducted linking BMI to life expectancy show a wide range of outcomes, including many studies that show you live the longest at BMI 27. And being underweight is actually much more problematic than overweight in terms of longevity. Right now there are doctors all over the country telling people to lose weight to improve their health when those people will have longer lives if they do not lose weight.
