Be Careful Out There

How Megan McArdle responds to valid, fact-based criticism: she mocks it.

A typical dialogue on diet goes something like this:

Expert: We don't have any known way to make obese people thin except gastric bypass surgery, which has a 2% mortality rate by itself.

Thin person: But I am very thin!

That's about 50% of the conversation in the comments to the Paul Campos interview. It's about as useful as the following exchange:

Expert: We don't have any known way to make short people tall, except for extreme surgeries and hormone injections.

Megan: But I am 6'2"

This is followed by a long line of straw men, tilting listlessly in fields reeking of rotting stubble, their fixed, painted grins staring balefully at nothing. McArdle bats her mighty enemies around for a while and finally plants her lance in the ground and declares victory.

Why is McArdle creating arguments instead of addressing arguments? When your ideas are not sound you can't defend them, so you create arguments that you can defend. McArdle starts off with a faulty premise--people can't lose weight--and must use faulty arguments to defend it.

Fat tissue makes people want to eat--it sends out for takeout. And hunger is a signal on par with thirst or pain. You can ignore it, if you have sufficient willpower. But just as most people can't withstand torture (a minority can), most people can't ignore the constant demand from their body for food.

[yap]

If when eating a normal 2,000-2,500 calorie diet, you do not spend significant amounts of your day fixating on food--fantasizing about it, binging, hiding it, strategizing how to procure it--you do not have anything interesting to say to someone who is struggling with obesity. You do not have better willpower than they do. You do not "care about myself" more. You are not more "serious about a healthy lifestyle" because you took off the eight pounds you gained at Christmas. You are no more qualified to lecture the obese on how to lose weight than I am qualified to lecture my short friends on how to become tall. You just have a different environmental and genetic legacy than they do. You're not superior. You're just somewhat thinner.

To put it another way: I have NEVER had a BMI above the normal range. How much more awesome am I than you? 30%? After all, you have to work at it. My willpower is apparently 100% natural.

In other words, if you disagree with McArdle you are acknowledging that she is moral superior. However, if you agree with McArdle you are acknowledging that she is genetically superior. It's funny how that works out.

So according to McArdle, it's impossible to lose weight because people can't control their appetites, ever. People just don't lose weight. Ever. There are enough reasonable points in McArdle's posts to make it easy to forget this main point--a Libertarian law professor says the government is too intrusive regarding nutrition, because it wants to control fat people using shame. This fits all of McArdle's preconceptions and vanities so she accepts it wholeheartedly.

McArdle has made the same point before:

This partakes of a mental model of obesity that casts it as a matter of simply making good choices from the available basket. Choose the salad, you stay thin; choose the steak, you get fat. That model is popularized by diet books and nutritionists, who are in the business of telling you what choices to make. The logical conclusion is that the reason the poor are obese is that they are either making bad choices, or their basket of choices is too restricted to allow them to choose low-calorie foods.

This model is being upended by research on appetite and metabolism. People's bodies have a set point that they very much want to maintain; if you push their bodies below the set point, their appetite will increase until it is nearly unbearable. A few superhuman people can withstand it, but hunger is an evolutionary response of the same order as pain: unless you're superhuman, you cannot overcome it with willpower.

There you go. Natural selection means you will become unbearably hungry if you cut your caloric intake and evolution will drive you to make it up with a Krispy Kreme later. Which makes this seem rather odd:

Over the last few months, I have virtually totally lost my sweet tooth. This also happened to my mother when she was in her thirties, and I could never understand it--how could you not want dessert? Now, suddenly, I'm just not interested. I'm not revolted, or anything; I'd just rather fill up on dinner.

Something that didn't happen to my mother is that I'm also losing my taste for processed carbohydrates; I've virtually stopped eating bread, and pasta and rice are falling farther and farther down the menu.

Of course, I should be thrilled--my body is naturally demanding one of those healthy diets I keep reading about. Except . . . there's something a trifle sad about never even wanting what used to be the best part of the meal.

As Joyce Davenport said on Hill Street Blues back in the day, "Some of us change. Others mutate."