Eating behaviors among Norwegian schoolchildren in relation to gender and socioeconomic status

Abstract

Eating behaviors are closely related to the risk of developing several chronic diseases such as cardiovascular diseases (CVD), several cancers and diabetes type II. Improving eating behaviors are therefore important to reduce the incidence of these diseases. According to the national guidelines on dietary intake in Norway the consumption of fruits and vegetables (FV) is low whereas the sugar-sweetened soft drinks consumption (SDC) and other unhealthy food items are high both among adults and children. As eating behaviors are established during childhood/adolescents and track well into adulthood, these are important periods to initiate and sustain healthy eating behaviors in order to obtain a maximum preventive effect on diet related diseases later in life. Both among adults and children there are large gender and social disparities in eating behaviors – i.e. boys and lower socioeconomic groups having less healthy eating behaviors. Exploring why we observe these differences is of great importance in order to make efficient interventions in the future to improve the eating behaviors of these groups.<br> The overall aim of this thesis was to study gender and socioeconomic disparities in eating behaviors and in determinants of eating behaviors among Norwegian pupils.<br><br>

This thesis includes data from two cross sectional surveys among Norwegian 6th and 7th graders participating in the Fruit and Vegetable Makes the Mark project (FVMM). The sample sizes include 27 schools participating in 2001 (1488 pupils) and 27 schools participating in 2008 (1339 pupils). The thesis also includes data from a third follow-up survey of the 2001-pupils in 2005. The pupils were then in 9th and 10th grades and this study sample include 33 schools (2870 pupils). In all surveys data was collected by questionnaires including a 24-hour recall of FV intake, a food frequency questionnaire (FFQ) of FV intake, SDC and other healthy and unhealthy food items, as well as questions on potential determinants of the intake such as perceived accessibility at home, preferences, attitudes and modeling. In the 2001 and 2008 surveys similar data was also collected from the parents by a parent questionnaire. Between 2001 and 2008 official school fruit programs were initiated in Norway, and in 2008 the schools therefore differ according to the pupil’s accessibility of FV at school. At some schools the pupils received a fruit or vegetable every school day (either through a free school fruit program or a subscription program) whereas other schools had no such program. The results from the 2001 and 2008 surveys are presented in paper II and III.<br> The results from the third follow-up survey in 2005 are presented in paper I and IV.<br><br>

Assessed by the 24-hour recall the results showed that the FV intake among the 6th and 7th graders had increased from 2001 to 2008 (paper II). The highest increase was observed among the pupils at schools which participated in a free fruit program and the effect of this program was the same regardless of gender and SES. Among the pupils at schools not participating in any fruit program there had been a less profound change in the pupils FV intake during the same period. The effect observed was mainly due to an increase in the pupils’ fruit intake whereas their vegetable intake still remained low.<br><br>

When assessed by the FFQ’s the results showed that the FV intake had slightly decreased from 2001 to 2008 (paper III). For the same period we found that the mean scores of perceived accessibility at home and preferences of FV had increased, and mediation analyses indicated that the decrease in FV consumption was suppressed by the increase in accessibility and preferences. Subgroup analysis showed that the FV intake had decreased among pupils with parents of lower educational level and slightly increased among pupils of parents with higher educational level – i.e. the social disparities in FV intake over time had increased. This increased disparity over time was partly mediated by an increased disparity in accessibility and preferences.<br><br>

Results from the third follow-up study showed that few pupils reported to eat FV at school while a large proportion of the pupils reported to consume snacks, sweet bakery and soft drinks at school (paper I). The girls and pupils planning to attend higher education after secondary school consumed FV more often, and unhealthy foods less often, than boys and pupils without plans of higher education. Large between-school differences in eating behaviors at school were also observed.<br><br>

Gender and SES disparities in SDC were observed in our study sample. The gender differences in SDC among the pupils in the third follow-up study were strongly associated with gender differences in attitudes and preferences whereas the pupils’ educational plans differences in SDC were strongly associated with educational differences in accessibility and modeling (paper IV). Both the gender and educational differences in SDC were partly mediated by accessibility, modeling, attitudes and preferences. Further, the results showed that both gender and educational plans moderated the associations between attitudes, preferences, accessibility, modeling and SDC.<br><br>

The results from this thesis confirm previously reported gender and SES differences in eating behaviors among children and adolescents. These differences in eating behaviors were also found among the pupils at school and were observed both regarding FV intake, SDC and their potential determinants. Further, it also shows that the social disparities in FV intake has increased over time, partly explained by increased disparities in perceived accessibility at home and preferences of FV among the pupils. However, the national school fruit program showed no significant difference in the effect of the program in relation to gender or SES, and free school fruit appear to be effective in increasing all groups of pupils’ fruit intake.<br><br>

More research on gender and social difference in eating behaviors among children and adolescents is needed, especially longitudinal studies and interventions studies focusing on how to improve eating behaviors among boys and lower SES groups.