Dietary intake, leisure time activities and obesity among adolescents in Western Sweden: a cross-sectional study.

BACKGROUND
Overweight and obesity among adolescents are increasing worldwide. Risk factors include dietary intake characteristics and high levels of physical inactivity. In Sweden, few large comprehensive population-based surveys of dietary intake and lifestyle among adolescents have been carried out. Thus, the purpose of the current study was to describe dietary intake and food choices as well as leisure time activities in relation to overweight and obesity in a total sample of all schoolchildren aged 15 years in Western Sweden.

METHODS
In 2008, a questionnaire was sent to all 21,651 adolescents born in 1992 in Västra Götaland Region, Sweden. Participation rate was 54.3 % (50.7 % girls/49.3 % boys). The questionnaire included a 73-item semi-quantitative food frequency questionnaire and questions on lifestyle. Results were evaluated against the Nordic Nutrition Recommendations and Swedish indicators of healthy diet and exercise habits. Associations with concurrent overweight and obesity were evaluated in multiple linear regression analysis.

RESULTS
Among girls, 49.5 % reached the goal of consuming fruit and vegetables at least daily, whereas for boys the figure was 34.4 %. Among both sexes, 15 % reached the goal of consuming fish at least twice weekly. Two-thirds of both sexes reached the goal of regular moderate or vigorous physical activity weekly. In total, 12.4 % were overweight and 2.4 % were obese. More girls than boys were underweight, whereas more boys than girls were overweight or obese (p < 0.001). Boys exhibited a more frequent intake of sodas and concentrated fruit juices, milk 3 % fat, bread and potatoes and fast food (p < 0.001). Frequent intake of candies and chocolate was reported by both sexes. Among girls and boys, living in rural areas, living in apartments and reporting no frequent leisure time physical activity were significant risk factors for being overweight or obese, also when adjusted for other risk factors.

CONCLUSIONS
Dietary habits of adolescents in Western Sweden warrant improvements. Public health actions should be taken to increase consumption of fruit, vegetables and fish, and decrease consumption of sodas and candies and also to increase frequency of physical activity. These actions may be helpful in reducing risks for overweight and obesity.