Obesity and Overeating: How to Break a Bad Habit

Scientists' advice on breaking bad habits.

September 06, 2011, 5:37 PM

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.

None of the participants, including the habitual popcorn eaters, cared much for the stale stuff, even though they were in a cinematic setting. Bottom line: Taking away even a small cue, like the setting or the hand used to eat the popcorn, overwhelmed the habit, apparently because the participants had to think about what they were doing.

Numerous other researchers have documented the strength of habits. Scientists at Cedars-Sinai Medical Center in Los Angles found that the best way to get into a regular exercise program is to "train the mind" first. The part of the brain that establishes a habit is packed in a small section at the base of the brain and billions of neurons located there respond quickly to repetition. So start today, do a little on a regular schedule, and soon it will become a habit, making exercise a routine part of the day.

"On average, people have more good habits than bad," Neal, who has since left USC to do research in a private company, said in a telephone interview. But bad habits can be particularly destructive, contributing to the current obesity crisis, he added.

That midnight snack, he added, may be nothing more than the result of snacking at midnight often enough that it becomes a habit. When the right time rolls around, it's time for a snack, even in the absence of hunger.

His formula is pretty simple. Put the cookie jar where you can't see it. Look only at the salad menu while in your favorite restaurant, but only if you don't have the habit of eating a great steak there every Friday night. And it isn't just a matter of willpower.

"Basically, it's not really a matter of setting the right goals or having enough will power," he said. "Those things are valuable, but they don't really get you over the line. The critical thing to focus on is the environment," where you can bring stimulus under control by ditching that dang cookie jar.

So Mary Poppins probably had it right: a spoonful of sugar makes the medicine go down. But do that too often and the medicine will always taste like sugar. It will become a habit. You won't even have to think about it.

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