Unhealthy dieting may fuel weight gain in teens

Teens who try to control their weight by skipping meals or using laxatives are actually more likely to be overweight in later years, research indicates.

"We found that dieting, and particularly unhealthy weight control behaviors, were not effective in weight management over time, and were actually associated with weight gain," study author Dr. Dianne Neumark-Sztainer, of the University of Minnesota, told Reuters Health. "We concluded that dieting was ineffective and even dangerous," she added.

Previous researchers have also reported an association between dieting, obesity and eating disorders. In one study, researchers found that dieting adolescents - girls and boys - were more likely to experience weight gain than nondieters and in other studies, involving middle and high school girls, researchers found that those who dieted had a higher risk of becoming obese than those who did not diet.

Neumark-Sztainer and her colleagues further explored the association in a five-year study of 2,516 adolescents who completed Project EAT (Eating Among Teens) surveys in 1999 and 2004.

Responses to the 1999 survey indicate that over half (57 percent) of the girls and one quarter (25.3 percent) of the boys dieted and roughly 58 percent of girls and 31 percent of boys skipped meals, used laxatives or otherwise engaged in unhealthy weight-control behaviors. By 2004, however, 27 percent of girls and 25 percent of boys were overweight.

In fact, teens who used unhealthy methods of weight control in 1999 were about three times as likely to be overweight by 2004 than those who did not use any weight control behaviors, Neumark-Sztainer and her team report in the Journal of the American Dietetic Association.

These unhealthy dieters were also at a six-fold higher risk for binge eating with loss of control and were also much more likely to practice self-induced vomiting and to use diet pills, laxatives and diuretics than their peers, study findings indicate.

In light of the findings, "teens should avoid dieting and the adults in their lives need to help them to do so," Neumark-Sztainer advised. "Dieting tends to be a short-term, ineffective behavior," she explained, adding "we've all seen people say, 'I'm starting my diet on Monday so I can eat what I want now' or 'I broke my diet...so I might as well go all out.'"

"Instead, teens should be encouraged to engage in eating and exercise behaviors that can be implemented over a long period of time," Neumark-Sztainer told Reuters Health.

Adults should also model healthy behaviors for their children, focus less on their child's weight and more on his or her overall health, and provide a supportive environment whereby their children can freely discuss their weight concerns and other issues, according to Neumark-Sztainer. She refers to these actions as "cornerstone behaviors" families can engage in to help their teens achieve a healthy weight and positive body image, in her 2005 book, "'I'm, Like, SO Fat!' Helping Your Teen Make Healthy Choices about Eating and Exercise in a Weight-Obsessed World."