By Amy Norton

NEW YORK (Reuters Health) - Teenagers who underestimate the risks of smoking -- or overestimate the social value -- are substantially more likely than their peers to take up the habit, a new study suggests.

Researchers found that among 395 high school students they followed for two years, those who thought the health risks of smoking were fairly low, or the social benefits fairly high, were about three times more likely than their peers to start smoking.

The fact that these perceptions influence teenagers' likelihood of smoking makes sense, but until now it hadn't been clear whether this was the case.

"This is the first paper that really shows that perceptions truly predict behavior," senior researcher Dr. Bonnie L. Halpern-Felsher told Reuters Health.

The findings also show that teens' ideas about the long-term and short- term consequences of smoking are equally important, said Halpern-Felsher, an associate professor of pediatrics at the University of California, San Francisco.

Heart disease, lung cancer and chronic respiratory conditions are among the major long-term risks of smoking, while shorter-term problems include chronic cough, a higher risk of colds and social hassles like smelling like smoke.

In this study, teens who thought they had little chance of developing any of these types of problems were three to four times more likely to start smoking.

The findings suggest that anti-smoking messages aimed at teenagers should address the short-term risks, as well as the long-range ones, Halpern-Felsher and her colleagues report in the American Journal of Public Health. []

They note that the more immediate consequences of smoking -- even something as minor as "bad breath" -- may carry greater weight with teenagers than the health risks down the road.

The study also points to the importance of kids' ideas about the social benefits of smoking -- such as the notion that smoking will make them "look cool," Halpern-Felsher said, or feel more relaxed.

Adults shouldn't deny that smoking has social value among teenagers, she noted, but should instead help kids find other ways to get the social benefits they want.

SOURCE: American Journal of Public Health, online December 23, 2008.

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