Way smarter folks than me have duked this one out before, and while obesity has its own slot in the International Statistical Classification of Diseases (ICD-9), the debate of whether or not it's truly definable as a disease is often a heated one.
Personally I'd describe obesity as the natural consequence of placing a collection of truly ancient genes, genes forged over millions of years of incredible and constant dietary insecurity and upheaval, into an insane, calorific, modern day, dietary utopia. In other words? Obesity and overweight are our bodies' normal, natural, responses to the world they find themselves living in.
But unlike many other natural responses to our environments, obesity frequently carries with it real risks to both quality and quantity of life. Yes there are certainly people even with class III obesity who are exceedingly healthy, but that truth certainly wouldn't negate the case for obesity as a disease as many diseases have varied penetrances, and for a large percentage, especially at its extremes, obesity carries marked medical impact.
So is obesity an actual "disease"?
While I'd happily argue that obesity is a disease of the modern day environment, I'll more happily argue that unless we label obesity a disease, even if you happen to think it's not, we're less likely to see real formative changes in the way we deal with and view obesity as a society.
The fact is that right now the accepted global viewpoint is that if obesity is a disease it's a disease of willpower, of gluttony, of sloth. Consequent to that viewpoint we see tremendous, hateful and harmful weight bias that starts as bullying in elementary school and continues unabated for life. Stereotype and bias targeting those people with obesity impacts upon their access to healthcare, employment, human rights and societal acceptance. Weight stereotyping also fuels the nonsensical weight loss quackery that steals money and hope, the well intentioned but misdirected public health campaigns that vilify obesity without offering tangible targets for change, and it's what allows medical schools and other allied health professional training programs, to virtually ignore thoughtful obesity related education - even if only to impress upon the students a non-blame based, you can in fact be fit and fat, approach.
Now there are indeed arguments that can be made regarding the risks of defining obesity as a disease, but when I've heard people discuss these risks, I've always been struck by the fact that those risks most commonly identified already exist. People already face discrimination by insurance companies consequent to weight, they already face difficulties with promotions/employment because of their weight, they already are labeled because of their weight, etc.
Were obesity to become accepted as a chronic disease, one that reflects a natural consequence of ancient genes in a modern day toxic environment, over time I would expect to see a change in societal attitudes. And there has been precedent for such a change - depression. The 60s and 70s saw society believing that people with depression need only, "pull themselves up by their bootstraps", yet now depression is readily accepted as a condition deserving of care, attention, empathy and most importantly, a lack of blame. Shifting the focus to obesity as a disease might also lead to environmental targeting of blame and consequently, environmental targeting of treatment.
My hope is that one day obesity will be seen as a modern day scourge, a day when the trite advice "all you need to do is eat less and exercise more" is seen by the general public as over-simplified nonsense, a day where obesity's not thought to be about personal weakness, a day where obesity's known to have a a wide and varied penetrance, a day where obesity's treatment would range from absolutely nothing in those with no medical consequences, to behavioural therapy, to drugs, to surgery, and one where allied health professionals were skilled enough to know when and if obesity's treatment was actually necessary.
A day when people who struggle with obesity aren't made to feel like if they just wanted it badly enough, they'd magically wake up with a mindset that ultimately would see them to permanent weight loss, because the thing is, one thing people don't lack is desire, and if desire and strength of conviction were actually all that were required, no one would be reading this blog post, and everyone would be whatever weight they dreamed of being.