The relationship between dental caries, sweet treat consumption and overweight: a longitudinal study in school-aged children

Background and objectives Dental caries and obesity are highly prevalent chronic conditions in industrialized countries and appear to carry a shared risk factor, that is, dietary sugar. This study aims to examine the longitudinal relationship between caries and overweight in school-aged children, and define the role of select sugary drinks and foods ("sweet treats") in that relationship. Methods We utilized data from the Finnish Health in Teens cohort study and included 3863 children with a mean (SD) age of 11.1 (0.8) years at baseline recruitment and information available on history of cavitated caries lesions (decayed, missing, and filled teeth on permanent dentition, DMFT) and body mass index (BMI). Children with DMFT = 0 were considered caries-free and those with DMFT>0 as having caries. Based on the BMI, measured at baseline and follow-up, we categorized the children into two groups: non-overweight or overweight according to age- and sex-specific cutoffs. Only children who were non-overweight at baseline were included in the study. We estimated weekly consumption frequency of sweet treats as a sum score. Using Cox regression, we defined the crude relationship between dental caries and risk of overweight at follow-up (model 1), and further considered the role of sweet treat consumption (model 2) and other possible confounders (demographics and physical activity; model 3) in that relationship, shown as hazard ratios (HR) with 95% confidence intervals (CI). Results Mean DMFT index was 0.7 (1.5). Of the children, 29.1% (n = 1126) had history of caries, and 5.6% (n = 217) became overweight during the mean follow-up time of 2.6 (0.8) years. Caries was not associated with becoming overweight either in the crude model (HR 1.07, 95% CI 0.81–1.42) or in the models controlled for sweet treat consumption (0.94, 0.80–1.24) or other possible confounders (0.94, 0.68–1.20). Conclusions This sample of school-aged children was caries-wise fairly healthy. Caries was not associated with development of overweight, and controlling the analysis for sweet treat consumption and other factors did not change that. Analyses should be repeated in populations with a poor caries status and with a longer follow-up time.