"It's not simply being overweight that leads to depression," Storch said in a telephone interview. "It's being overweight and getting a bunch of crap about it from peers that leads to anxiety or depression."
While one paradigm suggests weight leads to teasing, which then leads to psychological issues, another reverses those arrows to suggest depressed kids are less likely to exercise and more likely to gain weight.
In fact, Storch and his colleagues studied 100 overweight children and those at risk for being overweight, ages 8 to 18, to find out the effects of bullying. About a quarter of the children reported significant problems with bullies during the prior two weeks. The study, published in a 2007 issue of the Journal of Pediatric Psychology, revealed bullying often caused kids to avoid situations where they had been picked on, such as gym class and sports fields.
Storch's team also found bullied kids were more likely to be depressed, lonely and anxious.
"When you think about it, it makes intuitive sense, when you consider the hallmark signs of depression – sadness, fatigue, lack of interest in things you used to like," Storch said in a statement about the study. "When kids are having a tough time with peers, and struggling with depression, then this can translate to reduced rates of physical activity."