I started this post as a reply to the OrgTheory thread on obesity but it got long enough I decided to move it here.
With all due respect, I think the claim that “obesity is not the problem” is overstated. I suspect that this overstatement is due in part to medical sociology’s tendency to infer from the “social construction of <condition>” that <condition> is not really real (see here for more on that). (Quick disclaimer: I have not yet read Abigail Saguy’s What’s Wrong With Fat?, though I hope to soon.)
BMI is best understood as a screen for, not a measure of, obesity. Like other screens, it can be used in a clinical setting to flag possible morbidity. When Victor Oladipo shows up with a high BMI, that’s an example of a false positive in the screen, but it’s not evidence that the screen is generally false!
The structure of the claim is that obesity (measured however) is imperfectly correlated with health. That is, some healthy people are obese, and some obese people are healthy. Consider an analogy with beta-hemolytic streptococcus infection (“strep throat”). A substantial number of people–children in particular–have strep infections in the “carrier” state, meaning that a strep test reads positive, there are strep colonies in their throats, but they show no symptoms. They are strep-positive but “healthy” (in this respect). Of course, plenty of other kids don’t have strep but do have sore throat and fever. So streptococcal infection is imperfectly correlated with relevant health outcomes. Does it follow that streptococcal infection “isn’t the problem”, or that strep doesn’t cause sore throat and fever? Of course not. Similarly: my grandfather drank like a fish and chain-smoked until his death (from other causes) at age 89. It doesn’t follow that smoking and drinking are not causes of health problems.
I can think of several possible reasons why we could find imperfect correlation between obesity and health:
- Obesity isn’t the problem.
- Obesity is a problem for some subsets of the population, less so for others.
- Similar to the above, obesity complicates certain other conditions, so it is an additive health risk but perhaps not so much an independent health risk.
- The effects of obesity on health play out over the long term and so some such effects have yet to be observed.
- Obesity is a mediating factor between other health risks and health outcomes.
I’m sure there are others as well.
Saguy’s Time piece cites a 2009 study suggesting that BMI is about as good as other measures at indicating obesity. But the study also shows “excess deaths” associated with obesity; the main point of it is that BMI is a reasonably good measure of the risk of such excess deaths! A related editorial emphasizes that their estimate of excess deaths is likely low due to exclusion of comorbidities. And another recent article suggests that the so-called “obesity paradox” is present only among “obese NHANES male participants with a wide variety of serious illnesses”–not a very compelling case for discarding the general claim of obesity having health risks!
One of the strong implications is that there is a conflict of interest: big pharma has an interest in promoting obesity as a health concern because that will promote greater drug sales. But while I don’t doubt that this pathway exists, it is also the case that lots of skilled researchers and clinicians employed by universities and funded by federal peer-reviewed sources (e.g., not big pharma) understand obesity to be a health problem. That doesn’t necessarily mean they’re right, but it ought to give pause to the conspiracy theory under which big pharma has created a fake moral panic to sell more drugs.
Finally: the question of stigma about obesity is of tremendous importance, and the medical community is far from immune. I think it’s plausible that stigma may actually help perpetuate obesity, and the question of whether the disease moniker increases or decreases stigma is also really interesting–but I don’t think it’s a settled question at all. (My wonderful former student, Michele Easter, did some great related work on genetics and eating disorders for her dissertation.) Medicalization can plausibly reduce stigma as well as increasing it, so if the concern is (appropriately, IMHO) reducing stigma then that ought to be the goal in itself, not claiming that stigma raises the question of whether obesity is in fact a health problem.