Impact of Intermittent Fasting on Changes in the Salivary Microbiome and Dental Caries Risk: A Systematic Review
Keywords:
Intermittent fasting, Salivary microbiome, Dental caries, Oral health, Time-restricted eatingAbstract
Intermittent fasting (IF) is increasingly recognized for its systemic health benefits, yet its effects on oral health, particularly the salivary microbiome and dental caries risk, remain unclear. This systematic review synthesizes current evidence on the relationship between IF and changes in salivary microbiota and caries susceptibility. A comprehensive search of PubMed, Scopus, Web of Science, and the Cochrane Library was conducted through December 2024 following PRISMA guidelines. Study quality was assessed using the Newcastle–Ottawa Scale and the Cochrane Risk of Bias tool. Fifteen studies involving 1,847 participants met the inclusion criteria. The findings indicate that IF influences salivary pH, flow rate, and microbial diversity. Time-restricted eating was associated with reduced levels of cariogenic bacteria, particularly Streptococcus mutans, and increased beneficial commensal species. However, prolonged fasting durations were linked to decreased salivary flow and temporary reductions in pH, which may elevate short-term caries risk. Overall, IF demonstrates complex effects on the oral microbiome, with both protective and potentially adverse implications for dental health. Further longitudinal studies are needed to determine optimal IF protocols that balance systemic benefits with oral health preservation.
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