Aim: Dental caries is a biofilm-dependent disease resulting from the interaction between microorganisms, a susceptible host, and a cariogenic diet. The risk of developing caries lesions varies according to the individual characteristics and socioeconomic and cultural factors. The aim of this study was to evaluate the length of time of oral clearance of food from the occlusal surfaces of molars in preschool children. Materials and methods:Chocolate cookies or pieces of apple were distributed to 188 children aged 3 to 6 years, and the food retention was observed every 10 minutes for 1 hour. The degree of retention was ranked by scores: (0) total elimination, (1) partial retention, and (2) total retention. Results:Children 3 to 4 years of age took 30 minutes to eliminate the cookies from the surfaces of the teeth examined, while the children who were 5 to 6 years of age took 20 minutes. The lower molars needed more time to eliminate the cookies. All children eliminated apple in <10 minutes. Conclusion:The results suggest that in younger children, the food may remain in the oral cavity for a significant period of time.Clinical significance: As eating habits influence significantly the development of caries lesions, and cariogenic food directly changes the demineralization-remineralization process, the results of this study show the importance of counseling the families regarding the frequency, time, and type of food to be offered to preschoolers as a preventive measure to early childhood caries.