(UPDATED) Under stress, we all tend to seek comfort — sometimes in not-so-healthy ways — but a new study suggests that challenging experiences are as likely to promote good habits as they are to support bad ones.
In several different experiments, researchers including* Wendy Wood, a professor of psychology and business at the University of Southern California, found that under various types of stress, all types of habits got stronger — not just the ones that cause trouble.
“When your willpower is low and you have little motivational energy, you are likely to fall back into old, bad habits of eating too much and not exercising — but only if those are, in fact, your habits,” says Wood. “Our novel finding is that people fall back into good habits in just the same way.” The study was published in the Journal of Personality and Social Psychology.
Stress depletes willpower; indeed, the brain is wired so that extreme stress actually shuts down the higher regions involved in long-term planning and thoughtful consideration. That’s because those functions are superfluous when survival is at stake. When under threat, the brain relies on faster, more primitive regions whose behavior is largely automatic under such circumstances. Automatic doesn’t mean built-in, however: many of our automatic behaviors, like riding a bike or eating french fries when feeling anxious, become automatic through repetition.
“People can’t make decisions easily when stressed, are low in willpower or feeling overwhelmed,” Wood says. “These pressures limit our capacity to make decisions.” The default in those cases is to engage in habitual behavior, so, she says, “When you are too tired to make a decision, you tend to just repeat what you usually do.” And it doesn’t matter what that habit is.
The new research involved various types of habits and stresses. In one experiment, 65 UCLA students were followed for 10 weeks and asked about their breakfast and news-reading habits. During the first few weeks, they recorded how often they ate foods that they considered healthy, such as cold cereal, hot cereal and health bars. They also reported on their intake of what they labeled as unhealthy breakfast selections, including pastries, pancakes and French toast. In addition, they detailed whether they regularly read educational news sections like local and national news, or lighter fare like advice columns and comics.
The scientists gathered this data over several weeks, measuring how strong the students’ breakfast and news habits were at times when they weren’t facing stressful exams like midterms and finals. Later, they compared these choices with those made during exam periods.
And indeed, those who had strong habits — either healthy or unhealthy — engaged in those behaviors more when they felt stressed by exam periods. Whether it was eating French toast or health bars more regularly or reading news that they felt was important or a guilty pleasure, habitual behaviors increased under stress.
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A second experiment involved 72 students at Duke University. This time, they were asked to specify goals they were hoping to achieve, such as improving grades or fitness. They also detailed particular behaviors they engaged in regularly to reach their goals, as well as behaviors that might get in the way.
For two of the four days of the study, they were randomly assigned to try to perform as much of their daily behavior as reasonably possible using their nondominant hand. This task tends to deplete self-control because it requires inhibiting a strong habit. Once again, this stressful experience increased habitual behavior — whether it worked toward or against the students’ goals.
Another experiment, this one including 164 UCLA students who tracked their study skills, found that those with the lowest levels of self-control were most likely to have strong habits, but it wasn’t clear whether having less self-control led people to engage in more habitual behavior in the first place or whether relying more on habit reduces self-control.
“Our data show that stress and low willpower increased performance of both good and bad habits,” Wood says. “And this happened following all kinds of events that drain willpower — taking exams, completing difficult mental tasks, trying to perform everyday activities in an unusual way. Even people with chronically low levels of willpower and self-control relied more on habits.”
So why does it seem that only bad habits emerge when we face the cauldron of stress? Wood says it’s a matter of attention. “We don’t notice so much when we fall back into good habits — these are the ones that are working for us to meet our goals, and so they aren’t problematic. It’s the bad habits we focus on, and thus people are more aware of falling back into bad habits when their willpower is low.” The bad habits stand out more, in other words, because they tend to derail us from achieving our goals.
The findings may prove useful for reinforcing good habits that we cultivate to help our health. But that requires taking the time to establish these healthy behaviors before a challenging situation strikes. If you want your default to be to exercise when you stress out — rather than reaching for a doughnut — you have to hit the gym repeatedly.
“Getting enough exercise, eating right, getting enough sleep, not smoking — all of these should become an unthinking, automatic part of your day,” Wood says. “If they are, then you will continue to perform them even when your willpower is low and you can’t muster the energy to ‘do the right thing’ for your health.” The fact that habits are hard to break can work for you or against you.
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*Corrected to reflect that Wendy Wood is a co-author of the study, not the lead author, who is David Neal, founder of Empirica Research in Florida.