Adolescent girls who view themselves as unpopular have a higher risk of gaining weight in subsequent years, researchers have found.
The study asked more than 4,400 girls aged 12 to 18 how they viewed their status on the social ladder, from a scale of 1 to 10. Two years later, researchers compared the weight gained by those who ranked themselves as a 5 or higher, compared with the weight gained by those who ranked themselves 4 or lower.
Those who perceived themselves as unpopular were 69 percent more likely to gain two points on the body mass index scale in the two years that followed the questionnaire.
Lead study author Adina Lemeshow, project analyst for the New York City Department of Health, actually completed the study when she was a graduate student at the Harvard School of Public Health. The study was published in the journal Archives of Pediatrics & Adolescent Medicine
The study adds to past evidence that social and emotional factors -- including depression and low self-esteem -- are important contributors to obesity in adolescents. But it also takes these findings one step further by demonstrating that for many girls, feelings of social inadequacy precede weight gain.
"Ours is the first study to look at this data prospectively," Lemeshow says. "One question which had always come up was whether it wasn't the other way around -- in other words, how BMI would cause a lower social standing."
Childhood obesity experts who were not affiliated with the research agreed that the study gives a clearer picture of how emotional and social factors could contribute to risk of overweight and obesity.
"Previous studies have been 'snapshots' of children with low self-esteem, which found that they are more likely to be overweight," says Dr. Goutham Rao, clinical director of the Weight Management and Wellness Center at the Children's Hospital of Pittsburgh. "This study tells us that low self-esteem, in the form of low-perceived social status, precedes weight gain."
But some health experts point out that though the study findings are intriguing, more information is needed before it can be said for sure whether low social standing leads to weight gain.
"Do adolescents become obese because they are not popular, or do they become less popular as they gain weight?" asks Judith Myers-Walls, associate professor and extension specialist at Purdue University's department of child development and family studies. "It is likely that there is a cycle and that both things are happening. A much more detailed study would need to be conducted to explore what happens in the minds and bodies of the young women."
But while the study sheds light on social standing and weight gain in girls, the findings raise the natural question: Why might this be happening?
The answer may lie in the possibility that girls who don't enjoy popularity among their peers may feel they cannot reap significant rewards from maintaining a healthy weight.
"The most obvious connection that struck me was that girls with lower self-esteem do not believe they can benefit much from maintaining a socially acceptable appearance -- in other words, being slim," Rao says. "Therefore, they may invest less time and energy in good nutrition and physical activity, and gain more weight as a consequence.
"Slimness has an enormous social value among girls. If a girl doesn't value herself to begin with, being slim is unlikely to be a priority."