Now 13, Julia seems to have escaped the Girl Box. She eats a healthy diet without obsessing over food and loves to exercise for the fun and camaraderie of it. But for many kids her age, maintaining a positive body image is an ongoing challenge. In one recent study more than half of the 13-year-old girls and three-quarters of the 17-year-old girls said they were "unhappy with their bodies." That number climbs to 80% by the time girls reach adulthood. Although some girls complain about specific body parts ("my breasts are too small, my thighs are too big"), the overwhelming concern is not being thin enough.
Boys don't want to be overweight either, but being thin isn't as desirable as achieving a strong, athletic ideal. "Male models are now more buff and perfectly sculpted, and so are athletes such as basketball star LeBron James, acts such as Mark Whalberg, and singers such as Usher, whom boys look up to," says Linda Smolak, Ph.D., a professor of psychology at Kenyon College in Gambier, Ohio. "Compare them with teen idols of a generation ago—Michael Jordan, Tom Cruise or Jon Bon Jovi, none of whom was excessively muscular—and you see a major shift in body-image role models for boys.:
Unrealistic body ideas not only affect a child's self-image but also may lead her to try dangerous behaviors to achieve those standards. Recent research shows that close to half of girls ages 9 to 11 are "sometimes" or "very often" on diets, compromising their nutrition at a time when their bodies are rapidly developing. It becomes more pervasive into adulthood; 91% of college-age women report dieting. And these restrictive eating patterns can lead to eating disorders. Anorexia and bulimia typically start in the teen years and affect about 5 million to 10 million American girls and young women and about 1 million American boys and men, according to the National Eating Disorders Association.
When Harvard researchers studied more than 6,900 girls ages 9 to 14, they found that vomiting or taking laxatives to control weight increased 30% to 40% among girls who said they were trying to look like women on TV, in movies, or in magazines. And while these behaviors are less common in boys, a separate study found that boys are three times more likely than girls to use products such as protein powder or shakes, creatine (a performance-enhancing supplement), steroids, and growth hormone, especially if they also read health and fitness magazines featuring muscular male figures.