Teenagers who engage in binge eating or other disordered eating behaviors are not just going through “a phase,” but are likely to continue those unhealthy behaviors into young adulthood, a new study from the University of Minnesota has found.
In fact, some extreme weight-control behaviors — including the use of diet pills — are likely to increase as teenagers move into their 20s.
Obvious, you say? Perhaps. But this is the first study to actually track dieting and disordered eating behaviors from adolescence to young adulthood.
The study also confirms a sad fact about young people — particularly young women — and diet-and-weight issues. Some 20 percent of the young adult women in this study reported using binge eating, fasting, diet pills or other extreme measures to control their weight.
“It points out a need for prevention efforts to decrease the prevalence of these behaviors, preferably starting in adolescence,” said lead author Dianne Neumark-Sztainer, an epidemiologist and professor at the University of Minnesota’s School of Public Health, in a phone interview Thursday.
The study used data from the U of M’s Project EAT (Eating Among Teens and Young Adults), an ongoing research project that began surveying Minnesota teens about their dietary and physical activity habits in the late 1990s. This current study examined 10 years of data involving 1,257 young women and 1,030 young men. One-third of the participants were 12 to 13 years old at the start of the study and 22 to 23 years old at its end. The other two-thirds were about 16 at the start of the study and about 26 at the end.
The Project EAT data is particularly helpful because participants come from a wide range of racial, ethnic and economic backgrounds, said Neumark-Sztainer.
Here are some of the study’s key findings:
- About one-half of the young women and about one-quarter of the young men reporting dieting within the year previous to being surveyed. The percentage of women who said they were dieting remained fairly constant throughout the 10-year period of the study. But males in the older group (those who were 16 at the start of the study) became more likely to diet (up from 21.9 percent to 27.9 percent) once they hit their 20s.
- Extreme weight control behaviors — things like fasting, binge eating, and skipping meals — significantly increased for both female groups and for the older male group. At the beginning of the study, 8.4 percent of the youngest group of girls and 12.6 percent of the oldest group reported such behaviors. By the end of the study, about 20 percent of both groups were engaging in the behaviors. Extreme weight control behaviors among the older male group also climbed: from 2.1 percent to 7.3 percent.
- One specific behavior — binge eating — increased from 9.9 percent to 14.1 percent among the older female group and from 3 percent to 5.9 percent among the older group of males.
- The use of diet pills more than tripled in most of the groups during the 10-year study period. For example, at the end of the study some 12.4 percent of the youngest group of girls in the study reported using diet pills within the previous year — up from 3.3 percent when they were teenagers.
That diet pill finding particularly surprised Neumark-Sztainer. Why more young people might be taking diet pills is unknown (her study wasn’t designed to answer such questions), but it might because of increased exposure to diet-pill sales pitches on the Internet, she said, or because people in their 20s find it easier to purchase and pay for the pills than they did in their teens.
“We know it’s a problem,” she said. “The next step is to find out why it happened.”
Early intervention is key
The continuance of all these potentially harmful behaviors from adolescence into early adulthood points out the need for early and ongoing efforts aimed at preventing, diagnosing and treating eating disorders, Neumark-Szatainer said.
“Even though we need to be concerned about obesity, we need to be sure we’re going about it in the right way,” she said.
That means letting young people know that these particular behaviors are counterproductive. In fact, teens who diet and engage in unhealthy weight control behaviors are two to three time more likely to be overweight five years later than their non-dieting peers, said Neumark-Sztainer.
The study appears in the July issue of the Journal of the American Dietetic Association.