Years ago I had lunch with a woman whose father ran a chain of weight-loss clinics. They were very successful and he was often invited to give talks. He never accepted these invitations, his daughter said, because he was seriously overweight — like 300 pounds.

I was reminded of this by Tara Parker-Pope’s recent New York Times Magazine article “The Fat Trap”. Parker-Pope tells us she is “at least 60 pounds” overweight, a bit of brave honesty for which I give her credit. I give her less credit for unskeptically quoting expert after expert — her article is essentially a review of expert opinion. If these experts are as wonderful and accurate as she says (by repeating their ideas), why is she 60 pounds overweight?

She never answers this question. She doesn’t even seem to ask it. However, someone else asks it. “The Fat Trap” includes this:

In most modern cultures . . . to be fat is to be perceived as weak-willed and lazy. It’s also just embarrassing. Once, at a party, I met a well-respected writer who knew my work as a health writer. “You’re not at all what I expected,” she said, eyes widening. The man I was dating, perhaps trying to help, finished the thought. “You thought she’d be thinner, right?” he said. I wanted to disappear, but the woman was gracious. “No,” she said, casting a glare at the man and reaching to warmly shake my hand. “I thought you’d be older.”

I already knew it was “just embarrassing” to be fat. What’s interesting is that the story that follows this unremarkable idea doesn’t support it. Her date wasn’t saying she’s fat. Sixty pounds overweight is not surprisingly fat. The “well-respected writer” can’t possibly have been surprised simply by that. Her date knows this. He’s bringing up something that puzzles him (“if you know so much about health, why are you fat?”), a reasonable question. By “you thought she’d be thinner, right?” he means “you thought, because of her job, she’d be thinner, right?” Parker-Pope and her editor don’t notice this.

Parker-Pope continued to reshape reality in an interview she gave, which included the following:

Q. What were your hopes in writing “The Fat Trap”?
A. My hope was that people would leave the article feeling informed and empowered. . . . [I got the story idea talking] with Dr. Michael Rosenbaum at Columbia about the science of weight loss. . . . [He told me what dieters already know:] that most people who are fat, are going to stay fat. . . . The truth is: Once you’ve gained weight, it’s really, really hard for most people to lose weight and keep it off.

Is she sure this “truth” is empowering? To me it sounds discouraging.

The speed of the obesity epidemic — 30 years ago, Americans were much thinner — implies that the obesity epidemic has an environmental cause. Genes don’t change that fast. Something about the environment — something that controls weight — has changed. Not exercise. Thirty years ago, Americans probably exercised less than now. It is likely that something they ate kept them thin, without trying. Parker-Pope fails to understand this. Or at least failed to ask the experts she spoke to about it. What about the environment has changed? she should have asked. If I were her, I’d be angry. The obesity epidemic is 30 years old! Thirty f—ing years! Why is it taking so long to figure out the cause?

The length of the obesity epidemic reflects research failure. Against her own self-interest, she doesn’t grasp this. At the end of “The Fat Trap”, like a brainwashing victim, she says:

I do, ultimately, blame myself for allowing my weight to get out of control.

I disagree. She should not blame herself for not knowing how to stay thin — hardly anyone knows. No, her failure is journalistic: (a) not grasping that the obesity epidemic must be due to changes in what we eat (lots of people understand this), (b) not grasping this means there must be a way to be almost effortlessly thin (in the 1970s people were much thinner with little effort), and, above all, (c) not confronting the experts she interviews. Her insensitive date spoke an uncomfortable truth. Now she is failing to ask uncomfortable questions (why is it taking so long?) Much worse.

My theory of weight control says the crucial environmental change that caused the obesity epidemic was increased consumption of foods that produce very strong (= very fattening) smell-calorie associations. To produce a very strong smell-calorie association, a food must (a) have a strong smell (a strong “flavor”), (b) have quickly digested calories (e.g., a high glycemic index), and (c) have exactly the same smell each time. All three features, especially the third, are much more true of factory food, fast food, and junk food than of handmade food. Typical food processing almost always increases flavor (e.g., add spices) and speeds digestion (e.g., cooking). Factory and chain restaurant food processing produces much less variable flavor than ordinary human food processing. Exactly when the obesity epidemic started, there was a big shift toward factory and chain restaurant food. One reason was microwave ovens. Microwave entrees taste exactly the same each time. Another reason was an increase in eating at chain restaurants. The Shangri-La Diet goes into more detail.

At the end of “The Fat Trap” is this:

All the evidence suggests that it’s going to be very, very difficult for me to reduce my weight permanently.

No, not all the evidence. Alex Chernavsky used the Shangri-La Diet to lose 25 pounds and has kept it off easily and apparently permanently.