Teen-age girls who turn to appetite suppressants, laxatives, vomiting or extreme dieting to lose weight may be laying the foundation for future weight gain instead of shedding pounds, according to a study published in the December issue of the Journal of Consulting and Clinical Psychology (Vol. 67, No. 6).
Eric Stice, PhD, of the University of Texas at Austin, along with researchers at the Stanford University School of Medicine, studied dieting behavior in nearly 700 ninth-grade girls over a three-year period.
Controlling for initial body mass, the researchers evaluated the adolescents using self-report questionnaires and annual weight and height measurements.
They found that adolescents who reported heavy dieting and extreme weight-loss efforts, such as laxative use or vomiting, were more likely to gain weight over time and were at a greater risk for onset of obesity compared with teens who did not report such efforts.
One possible explanation for the findings, say the researchers, is that the girls who reported extreme dieting may have thought they were decreasing their caloric intake when in fact they were not.
"Many people who are dieting are already overconsuming," says Stice. "They aren't dieting effectively enough to offset the overconsumption."
The study also found evidence that bingeing and overeating lead to weight gain. This finding is exciting, says Stice, because a link between binge eating and weight gain isn't as obvious or as easy to demonstrate as some may think.
"Research indicates that obese people underreport caloric intake by about 30 to 35 percent," says Stice.
So, in studies that rely on self-reports, it's easy for subjects to "hide" bingeing and overeating by underreporting their caloric intake. However, this study showed that bingeing and overeating predict subsequent weight gain by directly measuring increases in girls' weight.
The findings suggest that more interventions and programs are needed to help teen-agers find better alternatives to drastic dieting, such as eating more healthful foods over time, says Stice.
For their next research project, Stice and his research team will examine weight loss in people who develop their own diet regimen compared with people who are placed on physician-structured nutrition and exercise programs.