Abstract: Introduction: The connection between ingestion of refined starches, particularly sugars, and the prevalence of dental caries is very well documented in the writing. So, the present study was carried out with an aim to determine if there is an association between body mass index (BMI)-for-age and dental caries in children and to find out the role of diet with respect to BMI-for-age and dental caries.

Methodology: A cross sectional study was conducted on 1000 school going children of 12- and 15-years age group. A cluster random sampling method was used to obtain the desired sample. Intra examiner reliability was observed using kappa statistics. Clinical examination was conducted in the school premises after obtaining informed consent from parent and permission of school authority. WHO 1997 proforma was used for recording dental caries. Body Mass Index was calculated The obtained data Was  analyzed using SPSS version 22.0 using Pearson correlation and linear regression test was used keeping p<0.05

Result: A negative correlation was obtained between Dental Caries and Body Mass Index of 12- and 15-year-old school going children.

Conclusion: The assumption that “overweight/obesity correlates with more caries” cannot be statistically proven. This study showed higher percentage of children was in the underweight category of BMI. Further, higher percentage of underweight children was in government schools as compared to private schools. Correlation analysis showed BMI had a negative correlation with DMFT. Many of the children can have a poor health status due to lack of knowledge about general and oral health. Continuous education and motivation of parents and children can help to some extent to improve their health status.