Last summer I had an experience that got me thinking about how much food we need to eat. I was in Paris with my Mom, and found that even though we were walking around most of the days, we only ate a couple meals per day. We had a breakfast, mostly of bread (you know the frogs and their bread) and then a regular meal in the afternoon. It was less than I would normally eat at home, yet I was never hungry.

The New Yorker blog has a post that connects to this, noting that why we get hungry is often unconnected to our need for energy.

More often than not, we eat because we want to eat—not because we need to. Recent studies show that our physical level of hunger, in fact, does not correlate strongly with how much hunger we say that we feel or how much food we go on to consume.
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Even if you’ve had an unusually late or large breakfast, your body is used to its lunch slot and will begin to release certain chemicals, such as insulin in your blood and ghrelin in your stomach, in anticipation of your typical habits, whether or not you’re actually calorie-depleted.

This probably doesn’t surprise anyone, indeed I think we all observe this. You’re not hungry at all but a plate of fried chicken passes before you and whammo—pig out city!

The article states that we start to see part of our environment as cues to eat. We have a great snack on our favorite couch and we become conditioned—like Pavlov’s dogs—to associate that couch with snacking. We drive to the dentist and are reminded how there’s a great donut shop nearby and we start to crave donuts. I think this is partly why I experienced so little food craving in Paris—it is a city unfamiliar to me and I had not programmed in the environmental cues to stimulate hunger.

On a side note, I recall reading about a very ineffective campaign against drug use that was set up by some city. (I read about this a while back; can’t recall the location.) The government placed billboards in ghetto neighborhoods saying things like “Cocaine: It’s Evil” and showing a big pile of cocaine. Of course the result was rehabbing drug users saw these signs and thought, “Oh man I would love to snort a pile of coke like that right now!”