RESUMO
BACKGROUND: The possible association between obesity, underweight, and dental caries remains in debate. In addition, the role of sugar consumption on the abovementioned relationship was little explored. AIM: This study aimed to investigate the relationship between nutritional status and dental caries in 12-year-old low-income children. DESIGN: This cross-sectional school-based study involved 406 12-year-old children living with limited economic resources. Dental caries was assessed using the decayed component of DMFT and PUFA/pufa index. Children were weighed and measured to assess nutritional status according to z-score/body mass index. Data on socio-economic and demographic characteristics, sugar consumption, sedentary behaviour, and psychosocial factors were collected through validated questionnaires. Multivariable multilevel Poisson regression was performed. RESULTS: Underweight children had 60% (RR = 1.60; 95% CI 1.13-2.57) higher mean of decayed teeth and had mean PUFA/pufa 2.8 times higher than children with normal nutritional status. Underweight children with high annual sugar intake had a greater mean of decayed teeth (RR = 2.72; 95% CI 1.46-5.06) than underweight children with low sugar intake. CONCLUSIONS: Our findings suggest that malnutrition is associated with dental caries among children from low-income families.