When social scientists connected the dots from a survey of adolescent health and a social network analysis, they found that overweight teens were more likely to be denied friendships from their peers that were of normal weight. Teenagers are more likely to socially exclude their peers who are overweight, which makes overweight youth have one less friend, on average, than normal weight youth.

The study, published in the American Journal of Public Health, outlines the complex social and biological relationships and perceptions that drive friendships between overweight and normal weight youth.

"We found consistent evidence that overweight youth choose non-overweight friends more often than they were selected in return," said David R. Schaefer, co-author and professor of the Arizona State University’ School of Human Evolution and Social Change.

Researchers poured over data that was collected from 58,987 students in 88 middle and high schools by the National Longitudinal Study of Adolescent Health. The average age of the students was 15, and 51 percent were female. They then looked at social network analyses to link different types of friend selection methodologies students used based on things they had in common, extracurricular activities, and those who met through mutual friends.

The weight of each student was then taken into account so they could isolate the factor and determine which types of weight classes were initiating friendships with who and if they were successful at it. Overweight youth were less picky when it came to what weight status categories their friends fell into. This led researchers to believe that when overweight youth reached out to normal weight peers for friendship and were rejected, not only did they reach out more frequently, but they were also rejected more frequently.

"This is especially troubling since friendships are important sources of support and companionship," said Sandra D. Simpkins, the study’s co-author and the professor of the T. Denny Sanford School of Social and Family Dynamics. "Not having or losing friends is associated with higher depression and lower self-worth for young people, which could exacerbate the health problems associated with being overweight."

Friendship rejection leads overweight youth to befriend other overweight youth, but only as their initial second choice. Researchers believe that rejection during formative teenage years can be especially difficult for those who are overweight. "Negative repercussions of not having friends may be more pronounced in middle- and high-school when intimacy and fitting into peer groups is critical," Schaefer said.

Experts suggest that parents learn how to talk about their own bodies or other people’s bodies. Many times overweight children have overweight parents and if the parent makes negative remarks about their own body, their child will likely follow the unhealthy self-fat shaming. Children, especially teenagers, do not have to be bullied in order to experience the pains of their socially-marginalizing weight.

In the past 30 years, childhood obesity has more than double in children between the ages of 6 to 11 and quadrupled in adolescents ages of 12 to 19 years old. In 2012, the Centers for Disease Control and Prevention estimated more than one-third of children and adolescents were overweight or obese. Learning how to live a healthy life can only increase the quality of life and interactions with others. Teenagers can manage their body size to some extent, but they cannot control how people react to the way they look. "It's important to keep in mind that overweight youth still have lots of friends. Having just one friend makes a big difference. And, it's less important how many friends teens have; what is key is that those friends are supportive," Simpkins said.

Source: Sanford D and Simpkins S. "Using Social Network Analysis to Clarify the Role of Obesity in Adolescent Friend Selection," American Journal of Public Health. 2014.