Background: In order to more effectively promote fruit and vegetable intake among children and adolescents, insight into determinants of intake is necessary. We conducted a review of the literature for potential determinants of fruit and vegetable intake in children and adolescents.

BackgroundLarge proportions of children do not fulfil the World Health Organization recommendation of eating at least 400 grams of fruit and vegetables (FV) per day. To promote an increased FV intake among children it is important to identify factors which influence their consumption. Both qualitative and quantitative studies are needed. Earlier reviews have analysed evidence from quantitative studies. The aim of this paper is to present a systematic review of qualitative studies of determinants of children's FV intake.MethodsRelevant studies were identified by searching Anthropology Plus, Cinahl, CSA illumine, Embase, International Bibliography of the Social Sciences, Medline, PsycINFO, and Web of Science using combinations of synonyms for FV intake, children/adolescents and qualitative methods as search terms. The literature search was completed by December 1st 2010. Papers were included if they applied qualitative methods to investigate 6-18-year-olds' perceptions of factors influencing their FV consumption. Quantitative studies, review studies, studies reported in other languages than English, and non-peer reviewed or unpublished manuscripts were excluded. The papers were reviewed systematically using standardised templates for summary of papers, quality assessment, and synthesis of findings across papers.ResultsThe review included 31 studies, mostly based on US populations and focus group discussions. The synthesis identified the following potential determinants for FV intake which supplement the quantitative knowledge base: Time costs; lack of taste guarantee; satiety value; appropriate time/occasions/settings for eating FV; sensory and physical aspects; variety, visibility, methods of preparation; access to unhealthy food; the symbolic value of food for image, gender identity and social interaction with peers; short term outcome expectancies.ConclusionsThe review highlights numerous potential determinants which have not been investigated thoroughly in quantitative studies. Future large scale quantitative studies should attempt to quantify the importance of these factors. Further, mechanisms behind gender, age and socioeconomic differences in FV consumption are proposed which should be tested quantitatively in order to better tailor interventions to vulnerable groups. Finally, the review provides input to the conceptualisation and measurements of concepts (i.e. peer influence, availability in schools) which may refine survey instruments and theoretical frameworks concerning eating behaviours.

Objectives: To investigate the internal consistency of the scales and the test -retest reliability and predictive validity of behaviour theory-based constructs measuring personal, social and environmental correlates of fruit and vegetable intake in 10 -11-year-old children. Design: Test-retest with one-week interval. Setting: Five European countries: Norway, Spain, Denmark, Portugal, Belgium. Subjects: Three hundred and twenty-six children completed the questionnaire during class hours. Results: For the total sample across all countries, the test -retest reliability was good to very good (intra-class correlation coefficient (ICC) . 0.60) for 12 out of the 15 fruit constructs and also for 12 out of the 15 vegetable constructs. Acceptable ICCs, ranging between 0.50 and 0.59, were found for the remaining constructs. Test-retest reliability was comparable across countries. Only in Portugal were some significantly lower ICCs found for some constructs (knowledge and barriers related to fruit, general self-efficacy related to fruit and vegetables) compared with the other countries. Cronbach's a values were moderate to high (range 0.52 to 0.89) with the exception of the general self-efficacy scale, which had a value below 0.50 for both fruit (a ¼ 0.42) and vegetables (a ¼ 0.49). Spearman correlations with intake ranged between 2 0.16 and 0.54 for personal determinants and between 0.05 and 0.38 for environmental determinants. Compared with other studies, predictive validity can be considered moderate to good. Conclusions: The questionnaire provides a reliable, valid and easy-to-administer tool for assessing personal, social and environmental factors of potential influence on fruit and vegetable intake in 10-11-year-olds.

Objective: To investigate potential personal, social and physical environmental predictors of daily fruit intake and daily vegetable intake in 11-year-old boys and girls in nine European countries. Subjects: The total sample size was 13 305 (90.4% participation rate). Results: Overall, 43.2% of the children reported to eat fruit every day, 46.1% reported to eat vegetables every day. Daily fruit intake and daily vegetable intake was mainly associated with knowledge of the national recommendations, positive self-efficacy, positive liking and preference, parental modeling and demand and bringing fruit to school (odds ratio between 1.40 and 2.42, Po0.02). These factors were associated fairly consistently with daily fruit intake across all nine European countries, implying that a rather uniform intervention strategy to promote fruit can be used across Europe. For vegetables, the pattern was, however, less consistent. Differences between countries in cooking and preparing vegetables might be responsible for this larger diversity. Conclusions: This study showed that especially a combination of personal and social factors is related to daily fruit and vegetable intake in schoolchildren. This shows that a comprehensive multilevel intervention strategy based upon a series of individual and social correlates will be most promising in the promotion of daily fruit and vegetable intake in children.

The objective of the present study was to evaluate the effects of the Pro Children intervention on schoolchildren's fruit and vegetable (FV) intake after 1 and 2 years of follow-up. The intervention combined a FV curriculum with efforts to improve FV availability at schools and at home. Effects were examined in a group-randomised trial among 1472 10 -11-year-old children from sixty-two schools in Norway, the Netherlands and Spain. FV intake was assessed by means of validated self-administered questionnaires completed before the intervention (September 2003), immediately after the first year of the intervention (May 2004) and 1 year later (May 2005). Data were analysed using multilevel linear regression analyses with age and sex as covariates. Significant intervention effects for FV intake were found at first follow-up in the total sample. The adjusted FV intake reported by the children from intervention schools was 20 % higher than FV intake reported by children from control schools. At 1 year later, a significant impact was only observed in Norway. Positive intervention effects on FV intake occurred both at school and outside school. We conclude that the Pro Children intervention is a promising means to promote European schoolchildren's FV intakes, but mainly fruit intake, in the short term. As shown in Norway, where the intervention was best implemented, the intervention might also result in longer-term effects. Further strategies need to be developed that can improve implementation, have an impact on vegetable intake and can secure sustained effects. Fruit and vegetable intake: Schoolchildren: School-based interventionsEpidemiological studies have shown an association of adequate intake of fruits and vegetables with decreased risk for CVD, obesity, hypertension and type 2 diabetes mellitus 1,2 . Moreover, fruit and vegetable intake in childhood has now been related to a reduced risk for stroke 2,3 . The WHO and FAO state that promoting the intake of fruit and vegetables has now become a global priority 4,5 . This is especially true in the case for schoolchildren since intake of fruit and vegetables among European children is lower than recommended 6 . During the past decades many school-based fruit and vegetable promotion interventions have been studied, mainly in the USA 7 -9