News Summary

A new study published online in advance of publication in the Journal of Adolescent Health reveals that persistent use of dieting and unhealthy weight control behaviors, such as skipping meals and taking diet pills, can lead to a greater increase in body mass from adolescence into young adulthood.

Quotes

“There is a great deal of pressure to be thin within our society, and many young people are concerned about their body shape,” said Division of Epidemiology and Community health professor Dianne Neumark-Sztainer, Ph.D., M.P.H., the study’s lead author and principal investigator for Project EAT. “Unfortunately, in order to conform to this ideal image, young people feel the need to start dieting early.  Our study found this can have severe implications on their weight as they get older.”

“While young boys and girls may think dieting will help them lose weight, data suggests they may be causing more harm than good in the long run,” Neumark-Sztainer said. “The high number of both boys and girls that engage in unhealthy weight control behaviors is deeply concerning and it is important to educate them on the potential dangers of these behaviors and their correlation to long-term weight gain.  The focus needs to be on healthful eating and physical activity behaviors that can be sustained over time, rather than unhealthy weight control practices.”

Full Text

MINNEAPOLIS / ST. PAUL (January 05, 2012) – A new study published online in advance of publication in the Journal of Adolescent Health reveals that persistent use of dieting and unhealthy weight control behaviors, such as skipping meals and taking diet pills, can lead to a greater increase in body mass from adolescence into young adulthood.

The study, conducted by University of Minnesota School of Public Health researchers, utilized data collected during the University’s Project EAT Study, and examined the dieting, eating and physical activity habits of more than 1,900 middle school and high school adolescents surveyed over a 10-year period. 

“There is a great deal of pressure to be thin within our society, and many young people are concerned about their body shape,” said Division of Epidemiology and Community health professor Dianne Neumark-Sztainer, Ph.D., M.P.H., the study’s lead author and principal investigator for Project EAT. “Unfortunately, in order to conform to this ideal image, young people feel the need to start dieting early.  Our study found this can have severe implications on their weight as they get older.”

Neumark-Sztainer and her colleagues found that 37.8 percent and 48.7 percent of female participants engaged in persistent dieting and unhealthy weight control behaviors respectively, while 10.3 percent of male participants reported persistent dieting and 18.7 percent reported persistent use of unhealthy weight control behaviors.

Study results also revealed that persistent use of dieting and unhealthy weight control behaviors directly resulted in larger increases in body mass index (BMI) over 10 years for both groups. For example, females using unhealthy weight control behaviors at two time points during the study period (i.e., persistent use) increased their BMI by 4.6 units as compared to 2.3 units among females not using these behaviors. Male dieters increased their BMI by 7.0  units compared with 3.5 BMI units among nondieters.

To arrive at their results, researchers examined not only the prevalence of dieting and the use of unhealthy weight control behaviors, but also the changes and trends in weight gain and dieting behaviors from adolescence to young adulthood. 

Study participants were surveyed on how often they dieted to lose weight and how often they used unhealthy weight control behaviors, which include fasting, trying to eat very little food, smoking cigarettes for weight management, self-induced vomiting, and the use of diet pills, food substitutes, laxatives and diuretics.  Those who continued to engage in these behaviors throughout the study period gained more weight over time than those who never used these behaviors or stopped using them over time.

“While young boys and girls may think dieting will help them lose weight, data suggests they may be causing more harm than good in the long run,” Neumark-Sztainer said. “The high number of both boys and girls that engage in unhealthy weight control behaviors is deeply concerning and it is important to educate them on the potential dangers of these behaviors and their correlation to long-term weight gain.  The focus needs to be on healthful eating and physical activity behaviors that can be sustained over time, rather than unhealthy weight control practices.” 

About Project EAT

Project EAT was designed to investigate the factors influencing eating behaviors, physical activity patterns, and weight-related problems of adolescents and emerging young adults. Through a greater understanding of the socioenvironmental, personal, and behavioral factors associated with diet and other weight-related behaviors during adolescence more effective nutrition interventions can be developed.

Project EAT III is funded by a grant from the National Heart, Blood and Lung Institute.