[Overweight among adolescents in Oslo].

BACKGROUND: Socio-demographic factors affect the prevalence of overweight, and differences in lifestyle could be the cause. Possible consequences of overweight, such as mental health problems may also vary by socio-demographic factors. The aims of the study were to identify overweight and mental health problems by socio-demographic group and lifestyle and a possible association between overweight and mental health. MATERIAL AND METHODS: A questionnaire survey (UngHUBRO) was conducted among 10th graders in Oslo in 2000 and 2001. The response rate was 88% (N = 7343). Self-reported height and weight were used to determine overweight/obesity according to international standards. The prevalence of overweight/obesity and mental distress by socio-demographic group was calculated, and associations between the two were adjusted for lifestyle (dietary habits, physical activity and inactivity) by logistic regression. RESULTS: The prevalence of overweight/obesity was higher among boys (12%) than among girls (7%), and there was an inverse association with the length of parents' education for both genders. The association between overweight/obesity and mental distress was statistically significant for girls. The ethnic differences in overweight/obesity were large, but not statistically significant. INTERPRETATION: The prevalence of overweight varied largely between socio-demographic groups. There was an association between mental distress and overweight among girls and there are marked differences in lifestyle between over- and normal weight adolescents.