Teenages Trying to Lose Weight End Up Being Fat

Teenage girls who try to lose weight through dieting, exercise, and use of laxatives or appetite suppressants, are more likely to become obese in later life, according to new research.

A three-year study, conducted by Dr Eric Stice of the University of Texas and colleagues from Stanford University in California, included 692 girls from grade 9 through grade 12, aged between 13 and 17.
Every year, the researchers interviewed the girls about their eating, exercise, and health habits and recorded their height and weight. At the beginning of the study, 16% of the girls said they were dieting, and 75% said they exercised at least a little to keep their weight down. Twenty per cent reported some fasting, and 12% admitted using appetite suppressants or laxatives.

Looking at the girls' growth curves over the study period, the research team found that those who were overweight at the beginning were no more likely to gain weight than those who were underweight.
But those who used appetite suppressants, laxatives, and vomiting to control their weight, and those who participated in binge eating, were more likely to gain weight than those who did not report these behaviors.

The investigators also found that 9th grade girls who said they were dieting were at least three times more likely to become obese than those who were not dieting. Girls who said they exercised to control their weight or who reported using appetite suppressants or laxatives were also more likely to become obese.
The authors note that the study findings agree with results from previous studies that found "dieting predicts weight gain in adulthood." The researchers described two possible explanations for their findings. First, even though the girls said they were trying to lose weight, they may not actually have been reducing their intake of calories, or exercising to a therapeutic level, and so did not actually lose weight.
Second, it is possible that the girls were aware of a tendency to become overweight, and had already started trying to control that tendency before the study began. Writing in the Journal Of Consulting and Clinical Psychology, Stice and his colleagues say further research is needed.