Genetic and environmental influences on body image, disordered eating, and intentional weight loss
Year: 2004
Type: dissertation
Study design: Observational Study
Abstract: AimsMany previous studies have shown that body size is strongly genetically determined.The rapid global increase in rates of obesity implies that environmental influences must also be important.In concert, disordered eating and eating disorders have become increasingly widespread in Western countries during the second half of the 20 th century.However, relatively little is known about genetic and environmental contributions to individual variation in weight control.The aim of this study was to explore the genetic and environmental contributions to breakfast skipping, body weight and shape concerns, and intentional weight loss attempts in a large population sample of young Finnish twins. MethodsThe participants, five birth cohorts of Finnish twins born 1975-79, were followed longitudinally from the age 16 to age 22-27.At baseline, the health habits of the twins were assessed using self-report questionnaires that included questions on weight, height, sociodemographics, various health habits, and breakfast skipping frequency.Simultaneously, similar information was obtained by a behavioral and medical self-report questionnaire from the twins' mothers and fathers.The twins received three follow-up questionnaires at ages 17, 18, and 22-27.The final fourth questionnaire assessed weight, height, intentional weight loss, eating styles, and many other nutrition-related variables.Body shape and weight concerns were measured using the Body Dissatisfaction and Drive for Thinness subscales from the Eating Disorder Inventory.Demographic and behavioral correlates of breakfast skipping, body shape and weight concerns, and intentional weight loss were analyzed using cross-tabulations and univariate and multivariable logistic regression models.The family-based sampling was taken into account in all analyses.Different structural equation modeling strategies were used to estimate genetic and environmental influences on body image and weight control patterns in twins; twin-family modeling was used to explore breakfast eating patterns in twins and their families. ResultsParental breakfast skipping was the strongest factor associated with adolescent breakfast skipping.In both adults and adolescents, health-compromising factors, such as smoking, infrequent exercise, frequent alcohol use, and a high BMI, were significantly associated with breakfast skipping.Breakfast skipping was associated with low family socioeconomic status in adults and adolescent boys, but not in girls.Additive genetic effects explained 41% (95% confidence interval [CI]: 21-63%) of the variance in breakfast skipping patterns in girls and 66% (95% CI: 47-79%) in boys, and common environmental effects 45% (95% CI: 23-62%) in girls and 14% (95% CI: 5-29%) in boys.Twin-family models confirmed that there are substantial additive genetic and shared environmental influences in addition to individual-
Source: Työväentutkimus Vuosikirja
Author: Anna Keski‐Rahkonen
Language: English
Subfield: Clinical Psychology
Field: Psychology
Domain: Social Sciences
Open Access status: green
OpenAlex ID: W2261243354