Consumption of ultra-processed foods and dental caries in Brazilian adolescents

This study aimed to evaluate the association between ultra-processed food (UPF) and dental caries, considering muscle mass (MM), bone mineral density (BMD), and oral hygiene habits (OHH) as mediators. This study has an analytical cross-sectional design with 2,515 adolescents (18-19 years). The main exposure - the UPF intake ratio - was established using the food frequency questionnaire. The outcome was the number of decayed teeth, according to the DMFT index. The model adjustment included socio-economic status (SES), frequency of physical activity, and concurrent risk habits (CRH) as potential confounders. Three latent variables were considered: SES (family income, economic class, household head, and adolescent education), OHH (gingival bleeding on probing index and visible plaque index), and CRH (alcohol and tobacco dependence). The analyses used structural equation modeling, estimating the standardized coefficient (SC) in three models: lumbar BMD(1), femoral BMD(2), and total BMD(3). UPF consumption had a direct (SC_model1=0.071, SC_model2=0.072, SC_model3=0.071; p < 0.05) and total (SC_model1=0.067, SC_model2=0.068, SC_model3=0.068; p < 0.05) effect on the number of decayed teeth. BMD and MM did not mediate the association between UPF and dental caries, but the indirect association mediated by OHH was significant in all analyses (p < 0.05). Dental Caries was explained in other specific pathways: SES→UPF→Dental Caries (SCmodel₁ = 0.009, SCmodel₂ = 0.008, SCmodel₃ = 0.009); SES→OHH→Dental Caries (SCmodel₁ = 0.033, SCmodel₂ = 0.033, SCmodel₃ = 0.034); CRH→UPF→Dental Caries (SCmodel₁ = 0.009, SCmodel₂ = 0.008, SCmodel₃ = 0.008); CRH→OHH→Dental Caries (SCmodel₁ = 0.029, SCmodel₂ = 0.027, SCmodel₃ = 0.027). Dental caries prevention should include encouraging good OHH, healthy eating, and developing equitable public policies in middle and low-income countries like Brazil.