Background: A few studies have investigated tracking of dietary patterns or nutrient intake in pre-school children, but no studies have been identified examining tracking of sugar-sweetened beverages (SSB), fruit and vegetable intakes in early childhood (1-7 year olds). The purpose of this study was to investigate changes and tracking of intakes of fruit, vegetables and SSB, and association between maternal education and dietary tracking, from 18 months to 7 years of age.
Methods: Longitudinal data from the nation-wide Norwegian Mother and Child Cohort Study, conducted by the Norwegian Institute of Public Health were used, including 9025 children participating at three time points (18 months, 36 months and 7 years). Frequencies of fruit, vegetables and SSB were assessed by questionnaire. Slightly different questions were used at each time point to collect information about intake. Maternal education was categorized into ≤ 12 years, 13-16 years, ≥ 17 years. Cross-tabulation, Spearman's rho and multinomial logistic regression were used for assessing change, tracking and differences by maternal education.
Results: Analyses by gender indicated largest changes for intake of fruit and SSB from age 18 months to 7 years. Fair to moderate tracking coefficients (Spearman's rho = 0.23-0.46) for intake of fruit, vegetables and SSB were found and children assigned to low, medium and high frequency of consumption at 18 months continued to be in the same group at age 36 months and 7 years. Children of mothers with low education consumed fruit and vegetables less often and SSB more often compared to children of mothers with high education at 18 months of age. Children with higher educated mothers had lower odds for increasing fruit intake or decreasing SSB intake, compared to children with lower educated mothers showing a stable intake.
Conclusions: The tracking coefficients for intakes were fair to moderate and differences in intakes according to maternal education were found already at age 18 months. This suggests that promotion of healthy dietary behaviours at an early age is important to prevent unfavourable dietary behaviours later in childhood. Moreover, it seems important to target mothers in nutrition interventions for improving dietary habits among children.