Dietary free sugar and dental caries in children: A systematic review on longitudinal studies

Background: Dental caries, as a multi-factorial problem, is prevalent among children. The aim of this review was to assess the association between dietary free sugars (DFS) consumption and dental caries in 6- to 12-year-old children in the recent longitudinal e vidence. Methods: In this systematic review, database search was performed in PubMed, Embase, ISI Web of Science and Scopus using the keywords "diet", "dental caries" and "school children".We considered the articles published in English from 2004 to 2019. After duplicate removal,title, abstract data basell text of all included papers were assessed by two independent reviewers. The quality of included papers was assessed using the Newcastle-Ottawa scale. Results: From 2122 papers, ten longitudinal studies were included. In the included studies, the consumption of 100% juice (daily), candy (more than once a week), and soft drink and sweet drinks (at bedtime) were highly associated with caries in children. In few studies, daily consumption of water and dairy products was reported to be protective. However, some studies reported non-significant association between consumption of different sugary items and dental caries. The quality of included studies was moderate. Heterogeneity was observed in the measurement of caries outcome, and data collection tool for diet assessment, and statistical measure, which impeded the meta-analysis of data. Conclusion: The methodology and results in the longitudinal studies on the association of dietary free sugar consumption and dental caries in schoolchildren were heterogeneous, which urge the need for further standard research protocols in this area.