Chicago ? Suicidal impulses and attempts are much more common in teenagers who think they are too fat or too thin, regardless of how much they actually weigh, a study found.

Using actual body size based on teens’ reports of their height and weight, the researchers found that overall, overweight or underweight teens were only slightly more likely than normal-weight teens to have suicidal tendencies.

But teens who perceived themselves at either weight extreme – very fat or really skinny – were more than twice as likely as normal-weight teens to attempt or think about suicide.

The study was based on a nationally representative 2001 survey involving 13,601 students in ninth through 12th grade. The findings appear in the June issue of Archives of Pediatrics & Adolescent Medicine, published Monday.

About 19 percent said they had considered suicide in the previous year, and about 9 percent said they had attempted it.