If you follow health-related news in the mainstream media or regularly read peer-reviewed scientific literature on obesity, weight loss, or health and nutrition and in general, you can confirm my observation that the phrase, “Obesity is associated with…” is bounced around so frequently, it gets more action than a metal pinball in a 1980s arcade. And in place of that ellipsis (the three little dots), feel free to put just about anything you like, because I can pretty much guarantee someone’s established an association between obesity and whatever that other thing is: heart disease, diabetes, cancer, depression, a flat tire on your way to work, and rain on your wedding day. (With apologies to Alanis Morisette.)
Note that word: association. Unless and until a firm chain of causation between two things has been established, researchers have to be very careful with their language. (Believe me, I know. In my other professional capacity, writing for a supplement company that is committed to sticking to the science, I have to get pretty creative with ways to stay safely within the confines of FDA regulations regarding the mechanisms of action of certain products. For example, I can never say something like, “This vitamin formula is specifically designed to help manage diabetes.” Instead of making that kind of “disease claim,” I have to stick to what is known as “structure/function claims,” which are super boring and tepid -- as in, “May help support healthy blood sugar levels,” or “Contains taurine, a compound required for healthy liver function.”) My point is, because no one wants to get sued, everyone has to skirt the legal edges of nutritional rhetoric.
But here’s the thing. Between you and me—just us friends here—we all know that when obesity researchers say “association,” they’re implying causation. They want to say causes. Obesity causes [insert-awful-and-expensive-health-condition]. But they can’t. Because it doesn’t.
That is, not usually.