Impact of Refined and Unrefined Sugar and Starch on the Microbiota in Dental Biofilm

AIMS AND OBJECTIVE: Sugar is not only associated with dental diseases but also, along with carbohydrates, is linked to various health issues including obesity, cancer, diabetes, heart, liver, and kidney-related diseases. At the same time, a polyphenol present in unrefined sugar and starch (UReSS) is shown to inhibit microbial growth and prevent biofilms and dental plaque. The question arises, “is sugar the causative agent for dental diseases, or is its refined form the cause?” The objective of this study is to conduct in-vivo studies of the impact of refined and unrefined sugar and starch on the microbiota of dental biofilm. MATERIALS AND METHODS: An in-vivo study was performed using saliva and dental biofilm samples collected from 75 healthy subjects. For this study, healthy volunteers (n = 75) were randomly divided into five groups and were given sweet meals either made with refined white sugar and white rice (ReSS) or with unrefined brown sugar and red rice (UReSS). This was followed by using or not using a polyphenolic mouthwash. Before and after 4 h of eating a sweet meal, the saliva and dental plaque were collected and the DNA was analyzed by 16s metagenomic sequencing. The results were expressed in fold change of bacteria from 0 to 4 h. Statistical analyses have been performed by logarithmic linear discriminant analysis (LDA), Student’s t-test, and Wilcoxon signed-rank test. RESULTS: Upon LEfSe and statistical analysis, in-vivo experiments clearly showed that UReSS significantly decreased bacteria associated with dental diseases. In contrast, ReSS showed a significant increase in Actinomyces, Streptococcus, and Selenomonas with a high LDA score (Log 4.2) and statistical significance (P < 0.003). Mouthwash significantly decreased bacterial taxa associated with diseases in both the ReSS and UReSS groups. The in-vivo study showed a significant increase and decrease in Streptococcus levels in refined and unrefined sugar groups, respectively. CONCLUSION: In conclusion, polyphenols aid in the prevention of dental caries. This study recommends using polyphenol-rich unrefined sugars and carbohydrates for both oral and general health. This study is the first of its kind to bring awareness to the effects of refined and unrefined starch and sugars on the oral microbiota.