Overweight children are the most common victims of teasing at school, a new Yale study finds.

The Rudd Center for Food Policy and Obesity conducted a study showing that obesity, more than prejudices such as sexual orientation or race, is the primary reason that high school students are teased by their peers. Published online in the November issue of the Journal of School Health, the study is the first to examine high school students’ observations of weight-based teasing, and experts say that components of these findings will help inform future programs to eradicate the stigma associated with obesity.

“There has been increasing attention to teasing and bullying toward youth, but weight-based bullying has been ignored in the national discourse on this issue,” said Rebecca Puhl, director of research at the Rudd Center and lead author of the report.

The study surveyed over 1,500 high school students in central Connecticut about the way they and other students treated obese peers. Of the seven forms of teasing measured, obesity was the most commonly-witnessed, followed by teasing due to sexual orientation, intellectual ability and race. Of the students, over 84 percent reported witnessing other students being teased, and over half recalled clear verbal and physical victimization. Though over 57 percent of students said they would feel comfortable intervening when they saw an overweight student being teased, less than half of those students who said they would feel comfortable intervening also said they often chose not to act in these situations.

“This study does not deliver a surprise — it DELIVERS an affirmation,” David Katz, director of the Prevention Research Center, wrote in an email to the News. “Bias and bullying are expressions of our culture; our culture tacitly condones anti-obese bias. That has to stop.”

In 2008 the Center for Disease Control estimated the national adolescent obesity rate to be 19 percent, a 4 percent increase since 2000. Puhl said the increased prevalence of obesity makes it more important than ever to understand weight-based stigmatization and discover different ways of addressing it.

Marla Eisenberg, assistant professor of pediatrics at the University of Minnesota, wrote in an email to the News that the United States’ higher-than-average obesity rate raises concerns about the vulnerability of so many youth to weight bias, which can have immediate and long-term consequences for their emotional, social and physical health.

“School faculty should take weight-related harassment as seriously as other forms of peer victimization such as hate speech or physical aggression,” Eisenberg wrote. “Understanding the different reasons why young people are bullied or harassed by peers is useful.”

Puhl said the study demonstrated the need for more awareness and education about weight-based teasing in schools and increased vigilance from educators to protect these students.

Sarah Stone, director of operations at Mindstream Academy — a boarding school for overweight students who feel uncomfortable in other academic settings — suggested that it is important to emphasize the environmental factors that contribute to obesity, so that obese students do not blame themselves entirely for their condition.

Her school’s curriculum emphasizes health-related activities such as cooking, gardening and sports, with the aim of “healing the whole person,” not just helping them lose weight, according to the academy’s website. The school, settled on a 43-acre campus in Bluffton, S.C., tries to boost obese adolescents’ self-esteem and help them develop healthier habits. Students lose an average of 50 to 60 pounds within four months of arriving, Stone said.

“Our kids do lose weight here, but that is sort of the cherry on top,” Stone said. “We try to teach compassion for oneself by trying to take optimal care for oneself.”

Stone said that public schools lacked the focus on health education which her school had, possibly as a result of budget cuts. Public schools, where obese students are not taught healthy eating habits and are too afraid to participate in gym class, remain unfriendly environments, she said.

Obesity is defined as having a body weight above 30 kg per square meter, compared to 18.5-25 kg per square meter in a person of healthy weight.