CHAMPAIGN, Ill. – Youth who diet at early ages and report at least mild depression are at increased risk of developing eating disorders and engaging in unsafe weight-loss behaviors in young adulthood, new research by Janet Liechty and Meng-Jung Lee at the University of Illinois suggests.
Liechty, an expert in eating disorders and body-image perception, is a professor of social work and of medicine at Illinois. Lee is a doctoral student.
Published in the International Journal of Eating Disorders, Liechty’s study examined the longitudinal impact of depression, body image distortion, dieting and extreme weight-loss behaviors during adolescence on dieting and eating pathology in young adulthood. Extreme weight-loss behaviors included behaviors such as vomiting or using laxatives or diet pills.
Over the seven-year period of the study, the prevalence of dieting and extreme weight-loss behaviors increased for both males and females, and the rates of extreme weight-loss behaviors among both sexes more than tripled.
“These findings point to the need to better understand the natural history of disordered eating behaviors from childhood through adolescence and into young adulthood,” Liechty said. “This could help identify sensitive periods for symptom progression and help to more effectively apply prevention and intervention efforts with young people at risk.”
Liechty’s research was based on a nationally representative sample of more than 14,300 young people in the U.S. Participants completed two in-home health assessments seven years apart – the first, when they were in grades 7-12 and another as young adults, between the ages of 18-26.
Participants reported if they had engaged in two types of weight-control behaviors – dieting to lose weight and extreme weight-loss behaviors – during the prior seven days. Adolescents that reported engaging in extreme weight-loss behaviors were excluded from the sample so that the researcher could assess the onset of these behaviors during the time studied.
As young adults, 27 percent of women and 11 percent of men reported dieting to lose weight. Overall, 4 percent reported using extreme weight-loss behaviors as young adults, up from 1 percent during adolescence.
Depressive symptoms among adolescents were assessed using a 19-item scale that asked participants to rate how frequently their behavior reflected symptoms commonly associated with depression, such as “I feel too tired to do things.” Mean scores ranged from 0-3.
Each incremental increase on the depression scale correlated with a 1.4 percent increase in the odds of young women and men developing extreme weight-loss behaviors in early adulthood, Liechty found.
Dieting at an early age had a similar effect – multiplying young women’s odds of developing extreme weight-loss behaviors by 1.6 percent. Early dieting also increased the risk of binge eating and extreme weight-loss behaviors among women.
Young adults were asked to report if a doctor had ever told them that they had an eating disorder, such as anorexia or bulimia, and, consistent with prior research, this was used as an indicator of eating disorder diagnosis. The prevalence of disordered eating among young adults ranged from 2 to 6 percent, with binge eating the most common type among both sexes.
Early dieting increased the risk of binge eating and extreme weight-loss behaviors among women only.
Adolescent depression was a potent risk factor for young adult eating pathology. Depression was strongly associated with binge eating and eating disorder diagnosis for both sexes in adulthood. For each incremental increase on the depression scale, women’s odds of being diagnosed with an eating disorder doubled – while men’s odds multiplied six-fold. Compared to females, adolescent males with depression were more than twice as likely to report being diagnosed with an eating disorder.
“Most studies on eating pathology and depression have been conducted on girls and women, but this study adds to a growing body of work that has found similar associations for both genders,” Liechty said. “This underscores the importance of addressing depression prevention and intervention among both men and women to improve health outcomes.”
Adolescent males with body image distortion – a discrepancy between their body mass index and perception of being overweight – were at significantly greater risk of receiving an eating-disorder diagnosis. However, for young females, extreme weight-loss behaviors and early dieting were the primary risk factors correlated with an eating disorder diagnosis or the onset of binge-eating symptoms.
The study also found that adolescent risk factors have a cumulative effect. With the addition of each adolescent risk factor, the prevalence of young adult dieting, binge eating, extreme weight-loss behaviors, and eating disorder diagnosis increased incrementally. For example the rate of young adult binge eating was 3 percent with one risk factor, 5 percent with two, 10 percent with three, and 14 percent with four adolescent risk factors. Cumulative risk for young adult pathology was found even after controlling for background influences.
“This study highlights the long-term impact of early psychosocial risk factors on disordered eating and unsafe weight loss strategies in young adulthood, and the importance of prevention,” Liechty said. “We need to promote effective emotional coping strategies and safe, non-stigmatizing, body-affirming approaches to healthy eating and weight management during adolescence.”
To contact Janet Liechty, call 217-265-0577; email jliechty@illinois.edu. The paper, “Longitudinal Predictors of Dieting and Disordered Eating Among Young Adults in the US,” is available online.
