Aug. 7, 2009 -- People who rely on sheer willpower to help them lose weight, stop smoking, or beat other addictions more often than not end up giving in to temptation, and now new research may help explain why.

The study found that people tend to overestimate their ability to resist strong urges, and that those who are most confident about their willpower are most likely to lose it.

Rather than rely on self-control in situations where temptations arise, the best way to stay in control is to avoid those situations altogether, says psychologist and lead researcher Loran Nordgren, PhD, of Northwestern University’s Kellogg School of Management.

“The key is simply to avoid any situation where vices and other weaknesses thrive and, most importantly, for individuals to keep a humble view of their willpower,” he says in a news statement.

Nordgren and colleagues conducted a series of experiments on college students examining their reactions when exposed to temptation.

In one experiment, smokers who most strongly believed they could resist the urge to smoke were twice as likely to light up a cigarette as were smokers who perceived themselves as having low self-control.

In another test, hungry students more accurately predicted their ability to resist a future tempting snack than those who were not hungry, suggesting that the absence of hunger pangs makes people overconfident about their power over food.

The findings, which appear in the upcoming issue of the journal Psychological Science, have implications for anyone trying to overcome addiction, be it to food, alcohol, drugs, sex, or any number of other behaviors, Nordgren notes.

“We expose ourselves to more temptation than is wise, and subsequently we have millions of people suffering with obesity, addictions, and other unhealthy lifestyles,” he says. “And while our study focused on personal behaviors like smoking and eating, it is easy to apply our findings to a broader context.”