Obesity and Overeating: How to Break a Bad Habit

Sept. 7, 2011 — -- We humans are creatures of habit, both good and bad, and while habits can free us from having to rethink everything we do, every time we do it, they can also enslave us to activities that may be self destructive. They can be very hard to break, even when we know we must, but researchers at the University of Southern California have come up with a simple formula that may help, at least in some cases.

Don't try to overwhelm that bad habit with good intentions and a strong sense of self control, because it probably won't work. Instead, alter the environment that triggers that automatic response, which we call a habit, because without the right cues it may slowly go away.

All it took was a bag of stale popcorn, a movie theater, and surprisingly little manipulation to get habitual popcorn addicts to mend their ways.

Psychologists David Neal and Wendy Wood have studied habits for years, going back to the days when they were fellow researchers at Duke University. Coincidentally, they both relocated to USC a couple of years ago to continue their work on the powerful forces that control much of our activities as we breeze through life on autopilot.

We don't have to think about habits. They "are the bedrock of everyday life," relieving us of the need to plan, guide, and motivate "every action from making that first cup of coffee in the morning to sequencing the finger movements in a Chopin piano concerto," as they noted in one study.

In their latest study, published in the current issue of the Personality and Social Psychology Bulletin, Neal and Wood and several colleagues wanted to find out if persons who nearly always eat a bag of popcorn when at the movies would eat the stuff, even if it was really old. Just because it's a habit.

They recruited several hundred participants, some who really wanted popcorn with a movie, some who sometimes wanted popcorn, and some who really didn't care. So each person attending a showing in a regular theater was quizzed on how much they liked popcorn, how hungry they were, and several other things. They were not allowed to sit near anyone else.

Half were given a bag of freshly cooked popcorn, and the other half were given a bag that had been sitting around for seven days, leaving it stale and not particularly appetizing. After the showing the bags were collected and weighed.

Participants who could take it or leave it left the stale stuff almost untouched. But habitual popcorn eaters ate the whole thing, regardless of whether their bag was new or stale. Was it just because they really liked popcorn? Apparently not, according to a second study.

Enter new recruits to watch a flick with a bag of popcorn in a somewhat different setting. This time the experiment was conducted in a meeting room, not a movie theater, so the cinematic mystique -- and the cues -- were missing. Even the habitual popcorn hounds ignored the stale stuff. Again, the only difference was the setting.

And in a third experiment, with other new participants, the researchers returned to the movie theater, again armed with fresh and stale popcorn. But in this case, the participants were instructed to eat the popcorn only with their "non-dominant" hand. Right handers, for example, had to eat with their left hand.