Body mass index, clusters of health behaviour among school-age children and young people in Sweden

Abstract

Background: A healthy lifestyle for children is important for future health. Aims: To identify temporal patterns of change in body mass index (BMI) and associated health behaviour among 6–16-year-old children and young people in Sweden. Methods: A quantitative design with longitudinal cluster analysis. Findings: School-age children and young people tended to maintain their BMI categories established at the age of 6 years or when they entered the fourth grade, and the categories were stable in age and gender over time. Conclusions: Healthy behaviours affecting BMI should be established before children begin school. Although slight changes in children's categories of BMI may occur once they reach school age, the categories established at preschool generally persist at least until the age of 16 years. Because school-age children and young people generally maintain their categories throughout their school years, early preventive work regarding BMI and health behaviour is needed with particular focus on overweight and obese children and young people.