association between body mass index and caries frequency among zahedan elementary school children

background: a balanced nutrition schedule provides the essential substances for proper oral health. objectives: the aim of this study was to investigate the association between dental caries and body mass index in 6-11 year-old children in zahedan. materials and methods: in this cross-sectional study 1213 children (670 girls, 543 boys) were included. body mass index (bmi) and clinical examination for determination of dft (decay filling teeth) index (based on who criteria) were taken. collected data were analyzed using the t-test, chi-square and anova. results: among children, 20.8% had low weight, 66.3% normal weight, 7.8% were overweight and 5.1% obese. in the low weight, normal weight, overweight, and obese groups, the mean ± sd values for dft were: 0.63 ± 1.1, 0.88 ± 1.36, 1.16 ± 1.33, and 0.87 ± 1.31, respectively. there was a significant association between bmi and dft (p = 0.005). the overweight group had higher dft compared to the low and normal weight groups. 13.5% of low weight, 12.2% of normal weight, 14.7% of overweight and 22.6% of obese children had dft = 0. there was no statistical association between bmi and being caries free (p = 0.4). conclusions: the mean dft in the overweight group was higher than low and normal weight groups. there was a statistically significant association between bmi and dft.