Remember that time in third grade when you called the pudgy boy in gym class "fatso?"

It wasn't just mean. It might have inflicted lasting wounds, according to a Yale University study released Tuesday that found that overweight and obese children who are subjected to verbal taunts and physical bullying are substantially more prone during childhood to suicidal thoughts, eating disorders and high blood pressure than their peers.

Yale clinical psychologist Rebecca M. Puhl and a colleague from the University of Hawaii at Manoa reviewed four decades' worth of psychological, social and medical research on childhood obesity — more than 100 studies. They discovered that taunts, shoves, and social isolation can wreak emotional and physical harm in childhood and possibly beyond that is distinct from the health consequences of being overweight.

"It's important to distinguish that it's the victimization and the teasing that are leading to these consequences," Puhl said, "and not the obesity itself."

The research, which appears in the July issue of the Psychological Bulletin, also found that the discrimination by children against their overweight peers is breathtaking.

One widely cited 1961 study, replicated 42 years later, asked 10- and 11-year-olds to look at six pictures of other youngsters and rank the order in which they would like to be friends with them. The pictures depicted a child in a wheelchair, one on crutches, another with an amputated hand, a fourth with a facial disfigurement. A fifth photo showed an average-weight child with no disabilities and a sixth showed an overweight youngster.

In both the 1961 study and the 2003 follow-up, the heavy child was resoundingly sixth in order of preference, and spurning of the overweight child was more extreme in the more recent study. Overweight children are regarded with disdain, branded as lazy, ugly, stupid, and sloppy— with the bias that they should be able to do something about the extra weight.

"There's a high cost for obesity, and it's not just around the physical challenges," said Dr. Nancy Rappaport, director of school programs at Cambridge Health Alliance. "It's also around the corrosive undermining of self-confidence and the ability to see the possibility for change."

The taunts — and the damage — appear to be most pronounced among the heaviest children. But the stigma isn't limited to youngsters who are significantly overweight; even children who are just a little bit heavy are subject to teasing, the researchers found.

Too often, specialists said, the teasing begins in the one place that should provide a sanctuary from harm: the home.