Stepping onto a scale may be useful for adults trying to track and control their weight, but for teens and young adults, frequent weigh-ins may cause depression, say researchers from the University of Minnesota.

“Self-weighing may not be an innocuous behavior for young people, particularly women,” wrote the researchers, led by Dr. Carly R. Pacanowski, in their new study.

Overweight and obesity are major public health problems. Because eating patterns develop early in life, the researchers behind University of Minnesota’s Project EAT (Eating and Activity in Teens and Young Adults) are attempting to identify the environmental, personal, and behavioral factors behind activity and eating specifically among teens and young adults. Sadly, during the past decade, results from Project EAT reveal the overall prevalence of obesity has increased, while ethnic/racial disparities have also escalated.

Rising Teen BMI Rates

Specifically, the most recent EAT 2010 survey revealed nearly 19 percent of girls and 26 percent of boys were at or above the 95th percentile for body mass index (BMI), the cut-off point used for defining obesity. Another 20 percent of girls and 16 percent of boys were overweight, according to the percentiles. For girls, obesity is most common among African-Americans, Hispanics, and Native Americans, and it is rising among Asian girls. For boys, obesity is most common among Hispanics, Asians, and Native Americans, with recent increases seen among African-American, Asian, and Hispanic youth.

Bottom line: 39 percent of girls and 42 percent of boys are currently overweight or obese, according to Project EAT.

To understand how just one behavior, self-weighing, plays into this disheartening trend, the current study surveyed 1,868 young adults in Project EAT. More than two thirds of the ethnically and socioeconomically diverse participants were not overweight, about a third were in middle school and two thirds in high school. Based on their BMI, self-reports, and psychological test results, the researchers assessed and ranked participants’ weight concerns, body satisfaction, self-esteem, and depressive symptoms. The team also studied participants’ extreme or unhealthy behaviors.

What did they discover? Among the girls, increases in self-weighing were “significantly related” to increases in weight concerns and depression, say the researchers. Getting on the scale frequently also linked to decreases in body satisfaction and self-esteem, according to the authors, plus some girls also reported extremely dangerous weight-control behaviors. Concluding, the authors of the study suggest one way their research could be put to good use by doctors and other health care providers.

Because stepping on the scale is not stigmatized, teens and young adults would probably feel comfortable reporting how often they weigh themselves (compared to, say, answering questions about depression or self-esteem). Self-weighing, the researchers concluded, might serve “as a proxy for investigating other, more concerning changes in well-being.”

Source: Pacanowski CR, Loth KA, Hannan PJ, et al. Self-Weighing Throughout Adolescence and Young Adulthood: Implications for Well-Being. Journal of Nutrition Education and Behavior. 2015.