Diet quality, physical activity, body weight and health-related quality of life among grade 5 students in Canada.

OBJECTIVE To assess how diet quality, physical activity and body weight are related to health-related quality of life (HRQOL) among children in the Canadian province of Alberta. DESIGN In 2008, we surveyed 3421 grade 5 students and their parents from 148 randomly selected schools. Students completed the Harvard Food Frequency Questionnaire, questions on physical activities, and had their height and weight measured. The HRQOL of the students was assessed using the EQ-5D-Y. Parents completed questions on socio-economic background and children's lifestyle. We applied multilevel regression methods to examine the importance of children's diet quality, physical activity and weight status for the EQ-5D-Y Visual Analogue Scale and for the EQ-5D-Y dimensions. SETTING The province of Alberta, Canada. SUBJECTS Grade 5 students. RESULTS Students with better diet quality, higher physical activity levels and normal body weights were statistically significantly more likely to report better HRQOL than students who ate less healthily, were less active or were overweight or obese. CONCLUSIONS The importance of diet quality, physical activity and body weight status for HRQOL may help justify broader implementation of school health programmes that promote healthy eating and active living, as these programmes will help reduce the burden of childhood obesity and improve quality of life.