Does school environment affect 11-year-olds' fruit and vegetable intake in Denmark?

It is often found that adolescents eat too little fruit and vegetables. We examined the importance of school for 11-year-olds' daily intake measured by food frequency- and 24-h recall questionnaires in Danish data from the European 2003 Pro Children Survey. Multilevel logistic regression analyses included matched student-parent-school questionnaire data (N = 1410) from a random sample of 59 schools and were conducted for fruit and vegetables separately: 1) without explanatory variables, to decompose the between-school and within-school variance; 2) with individual level covariates (socioeconomic position, parental intake, etc.) to examine if the between-school variance was attributable to different student compositions of schools; and 3) with individual- and school-level covariates (school availability of fruit/vegetables and unhealthy food) to examine the effect of context. Additional analyses stratified by gender and home availability of fruit/vegetables examined if school food availability influenced subgroups differently. Between-school variations were quantified by intra class correlations and median odds ratios. We found that 40% of the students ate >= 200 g fruit/day and 25% ate >= 130 g vegetables/day. Most of the total variance in students' intake occurred at the individual level (93-98%). There were larger between-school variations in vegetable intake than in fruit intake. Fruit and vegetable consumption clustered within schools to a larger degree for boys than girls. The between-school variance did not differ by home availability. Boys and students from high availability homes consumed more fruit and/or vegetables if enrolled in schools with access to fruit/vegetables and unhealthy food or contrarily with no food available versus schools with only fruit/vegetables available. The small school-level effects on 11-year-olds' fruit and vegetable intake imply that family level interventions may be more important and that the success of school interventions will rely on the degree of parental involvement. (C) 2009 Elsevier Ltd. All rights reserved.