I’m reading the book Mindless Eating, by Brian Wansink, a Cornell professor who studies how context affects the amount of food we eat.

Wansink is best known for his funny experiments, like the one where he rigged up a bottomless soup bowl from which you can eat Campbell’s tomato soup all day and never run out. Unsurprisingly, subjects given the bottomless bowl ate more soup than those eating from regular bowls. Similarly, Wansink found that people eat more popcorn from larger tub; that people eat more food in larger groups; and that you eat more M&Ms if the candy bowl is on your desk than if it’s six feet away.

Although Wansink’s research seems solid, and I haven’t finished the book yet, I’m a little skeptical. I’m not going to say, as so many of Wansink’s subjects do, that I’m too smart to be fooled into eating more by a bigger popcorn tub. I’m sure I’m just as gullible as anyone. But I do wonder about a couple things that have not been addressed so far:

* Wansink talks a lot about central tendency and very little about variability. That is, he reports that, on average, people ate 73 percent more soup when given the bottomless soup bowl, but I’m curious whether there were individual subjects who ate very little or no additional soup, and what do these people have that the rest of us don’t? (This is the purview of satiety research, a field that has produced a lot of interesting data but not a lot of practical results.)

* Did the people who ate 73 percent more soup compensate by eating less later in the day, after they had escaped from the lab?

It seems like people vary in their ability to stop eating when they’re no longer hungry. Young children are the champs at this. But many adults are good at it, too–at least as evidenced by the fact that they’re not gaining weight. Why?