Body dissatisfaction and dieting among Finnish adolescents: a 20-year population-based time-trend study.

Body image has an important role in the health and development of adolescents. Body dissatisfaction and dieting can become chronic and continue into adulthood. There is a lack of recent, comprehensive studies on ongoing trends on body dissatisfaction. This study assessed time-trend changes in self-reported body dissatisfaction and dieting among Finnish adolescents at four assessment points. Representative samples of adolescents (N = 6660) aged 13-16 years participated in school-based, cross-sectional studies in 1998 (N = 1458), 2008 (N = 2044), 2014 (N = 1809), and 2018 (N = 1349), respectively. The studies were similar in design, methodology, and geographical recruitment areas. Body dissatisfaction and dieting were assessed with a questionnaire including items derived from the DSM-IV criteria for anorexia and bulimia nervosa. From 1998 to 2018, dieting and fears related to gaining weight decreased among females. Body dissatisfaction reduced among females, and their wishes to become thinner became less prevalent. Consuming large amounts of food at one time consistently decreased among females and males and there were no changes in the rates of willful vomiting. The number of females in the 90th percentile with the most severe symptoms decreased. The results indicate that body dissatisfaction and disturbed dieting improved among females during the 20-year study. Despite these positive developments, the overall level of symptoms among females remained substantial, indicating that females have much higher levels of body dissatisfaction and dieting than males.