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"
Let's explore the possible rejoinders to this:
1. Obesity is increasing in the population, so it can't be genetic.
Well, average height is also increasing in the population. Does that mean that you could be as tall as me, if you weren't too lazy to grow?
Twin studies and adoptive studies show that the overwhelming determinant of your weight is not your willpower; it's your genes. The heritability of weight is between .75 and .85. The heritability of height is between .9 and .95. And the older you are, the more heritable weight is.
2. Height doesn't have anything to do with health.
Actually, it may. Being taller puts a greater strain on your circulatory, cardiovascular, and musculoskeletal systems. Tall people are prone to all sorts of problems at higher rates, especially in their back. That doesn't make it any more sensible to suggest that we need a public health campaign to help tall people shrink.
3. We don't have any good way to make people shorter, but we do know how to make them lose weight.
Actually, this is rubbish: we don't know how to lose weight. Some of the things Paul Campos is saying about obesity are controversial, but this isn't. Every single study which has attempted to make overweight people get thin without very risky surgery has failed completely and utterly. Fewer than 1% of patients ever keep the weight off.
Highly educated people who have managed to get their body weight down 5-10% from where their body naturally wants to be confuse what they are doing with what someone obese enough to cause significant medical problems would need to do, which is get their weight down 50% or more from where their body apparently wants it. They are not the same thing. The amount of weight loss that these sanctimonious slenderizers have achieved has no statistically significant health benefits. Let me repeat: losing twenty pounds will not make you healthier. If you have diabetes and high blood pressure, there is an extremely modest improvement in test results. Unfortunately, it's even harder for diabetics to lose weight than the rest of us.
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. Gina Kolata's Rethinking Thin describes it thus:
Every time the result was the same. The weight, so painstakingly lost, came right back. But since this was a research study, the scientists looked at more than just weight loss . . . they measured metabolic changes and psychiatric conditions and body temperature and pulse. And that led them to a surprising conclusion: fat people who lose large amounts of weight may look like someone who was never fat, but they are very different. In fact, by every measurement they seemed like people who were starving.
On every count, the weird, bizarre, almost depraved behavior that Ancel Keys reported when he studied young men who were deliberately starved in his experiment during World War II was just like what Hirsch observed among the formerly obese subjects at Rockefeller University Hospital. Something ws driving these people to regain their weight, and it was not a deep-seated desire to be fat.
Their metabolisms, for example, had changed so that they hung onto, clung to, every calorie that was consumed, making it harder for them to stay thin. Before the study began, the fat people had a normal metabolism--the number of calories burned per square inch of body surface was the same as for people who had never been fat. That changed substantially after they lost weight, with fat people burning 24% fewer calories per square meter of surace area than were used by people who were naturally thin.
The Rockefeller subjects also had a psychiatric condition that had been termed "semi-starvation neurosis". Hirsch's patients dreamed about food; they fantasized about food, or breaking their diets. They secreted food in their rooms. They daydreamed about food. And they binged . . . eventually more than fifty people went through the months-long process of living in the hospital and losing weight, and every one of them had the physical and psychiatric symptoms of starvation.
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.
I fearlessly predict that more than one person will respond with some variation on "there were no fat people in concentration camps/but I told you, I totally lost 20 pounds last year by taking up marathon running!" Yes, we could solve America's obesity problem by putting everyone in the country on sawdust bread and cabbage soup. We could also just shoot anyone whose BMI is over 28. Are these good solutions? Because short of that, we don't have much.