I often score the ugly mouthpieces of Big Food for faulty logic, especially when they recast reasonable positions as absolutes, so they can then “prove” their falsity. (Example: “There is no evidence that sugary soda is the sole cause of obesity, so soda taxes or other curbs are unreasonable.” Except, no one (except them) says it’s the sole cause. Just that it’s an egregious, unredeemable cause, and therefore a good place to begin attacking the obesity problem.)

But Big Food isn’t the only one who does it. Let’s look at Ragen Chastain’s recent post, The War on Ice Cream, a Parable, which argues a favorite hobby horse of Big Food: causality vs. causation. Just because obesity coincides with an increase in several life-threatening conditions, doesn’t mean obesity causes these conditions.

Great! Let’s say that. Obesity doesn’t cause these conditions. Chastain and Big Food should be pleased.

But is causality the only call to action? That’s what climate-change deniers argue: We can’t prove that human manipulations of the environment are causing the rise in global temperature, so we can — no, we should! — ignore the strong evidence that they are related. As Paul Simon put it, “Proof is the bottom line for everyone.”

I like proof. But just because correlation isn’t causation doesn't mean it’s not correlation! that would argue against strict curbs, i.e., everyone must be at BMI 27, or whatever. But it would argue for a curve, with concern and encouragement to change increasing as BMI does. (Disclaimer: BMI isn’t a great measure, but as long as it’s in heavy use, I’m going to use it.)

As I’ve said many times, Chastain is almost freakish [in a good way] as an athlete; she’s got dance moves I marvel at and will never even remotely approach. She forever undercuts the proposition that body size precludes health or athleticism.

However. Exceptional is an exception.

Most people who are very large because of how they eat are barely active, never mind athletic. I was more athletic than most, but I fell out of the gym habit much more often than I struggled into it, and even when I went, I coupled my visits with 12-inch steak-and-cheese rewards across the street. (“I go to the gym, but I can’t lose any weight!”)

Usually, I didn’t want to move much, because my feet hurt, my joints hurt, and I couldn’t keep up with the others. Whatever beauty I observed on a nature hike was sullied by the sweat, chafing, and heavy breathing. Far more people experience that than are able to pirhouette. 

Obesity has an incredible crosscurrent of causes, including heredity, upbringing, brutal food processing, opportunistic food formulation, relentless advertising and promotion. We’re never going to nail down the one cause, or the one set of causes. So waiting until we do is an unhealthy plan.