Sweeteners
added sugar causes dental caries
Strong support Sweeteners 🔬 Includes disconfirming
Part of: • Added sugar
RefutedContestedStrong support
consensus score 0.84
📅 Last reviewed: 2026-07-15 ⓘ
Evidence ladder
How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."
Top evidence so far: All trials, pooled (Meta-analysis)
MechanismIn-vitroAnimalObservationalRCTMeta-analysis
How the studies fall
14 support 0 contradict 5 tested null 0 mixed · 19 sources, 14 independent groups
What the evidence shows
The most firmly established harm of dietary sugar: free/added sugars — especially in sugar-sweetened beverages — are the primary dietary cause of dental caries, via acid produced when oral bacteria ferment them. Systematic reviews underpinning WHO guidance show a consistent dose-response, which is precisely why sugar-free sweeteners exist for oral care.
The evidence (19)
| Source | Grade | Stance | Quality | Finding |
|---|---|---|---|---|
| Lim SW et al 2025 · study_type: observational | observational | tested-null | low | 2-sample Mendelian randomization using GWAS data found no strong evidence for a causal effect of genetically predicted sugar intake on dental caries, whereas type 1/2 diabetes showed positive associations with caries independent of sugar. |
| Pamuk C et al 2026 · study_type: observational | observational | supports | low | Case-control study (24 ECC vs 34 non-ECC children) found frequency of sugar-containing foods/beverages >3x/day between meals was significantly higher in the ECC group (p=0.021), alongside elevated S. mutans and cathelicidin LL-37. |
| Moynihan & Kelly 2014 · J Dent Res | meta-analysis | supports | high | WHO-informing SR: restricting free-sugar intake reduces dental caries; consistent dose-response across the lifespan. |
| Filho RN et al 2026 · study_type: observational | observational | supports | low | Cross-sectional cohort (n=2515 adolescents) found sugar consumption had a direct effect on DMFT index (CP=0.049; p=0.016), alongside links to depression and socioeconomic status. |
| Candrea S et al 2026 · study_type: observational | observational | supports | moderate | Cross-sectional SALIVAGES study of adults found sugary beverages, refined carbohydrates, pastries, and donuts were strongly positively associated with DMFT decay index, among oxidative-stress/AGE biomarkers and smoking. |
| Dalugoda Y et al 2026 · study_type: observational | observational | supports | low | Epidemiologic-economic modelling study projected a 20% SSB tax in Egypt could prevent 30.9 million instances of tooth decay over 25 years, alongside reductions in obesity, T2DM, and cardiovascular events. |
| Nakamura K et al 2026 · study_type: animal | animal | tested-null | moderate | Rat study: hydrogel-encapsulated fructose-glucose sports fuel (BEADS 17.7%, GEL 21.9%) produced lower caries incidence than a control sugar formulation (CONT 39.6%) despite equal sugar content, indicating delivery matrix modulates cariogeni |
| Alrashdi M. 2026 · study_type: observational | observational | supports | low | Retrospective cohort (n=375 Saudi adolescents): unsweetened coffee drinkers had lower caries increment than sweetened-coffee drinkers (0.52 vs 1.09 mean DMFT increment, p<0.001) and non-consumers, suggesting sugar addition increases caries |
| Valenzuela et al. 2021 · Eur J Public Health | meta-analysis | supports | moderate | SR/MA: sugar-sweetened beverage consumption associated with higher dental caries and erosion. |
| Enax J et al 2026 · study_type: mechanism | observational | supports | moderate | Chemistry review explains that acidic environment (from bacterial fermentation of sugars/fermentable carbohydrates) drives dissolution of enamel hydroxyapatite via low pH and calcium-binding ligands, underpinning caries formation. |
| Hughes A et al 2026 · study_type: observational | observational | tested-null | low | Cross-sectional study of 88 elite Irish athletes (90% had untreated caries) found cariogenic starch intake from snacks, not sugar per se, was significantly associated with caries-risk cluster membership (p=0.005); mean sugar intake was 128g |
| Schlueter N et al 2026 · study_type: observational | observational | supports | moderate | German S3 clinical guideline on caries prevention in permanent teeth lists 'reducing sugar consumption' as one of seven core evidence-based recommendations for lifelong dental health, alongside fluoride and oral hygiene. |
| More SG et al 2026 · study_type: observational | observational | supports | low | Narrative policy review states excessive intake of free sugars is 'strongly linked' with dental caries (alongside obesity, T2DM, CVD) and argues for fiscal/regulatory sugar-reduction policy in India, citing global evidence. |
| Echeverria MS et al 2025 · study_type: meta-analysis | meta-analysis | supports | high | Systematic review and meta-analysis of cohort studies (17 studies, 9 pooled for meta-analysis) found sugar consumption in early childhood associated with early childhood caries; pooled OR=1.59 (95% CI 1.50-1.68), low risk of bias across inc |
| Moynihan 2016 · Adv Nutr | observational | supports | moderate | Review: free sugars are the key modifiable dietary cause of caries; effect scales with amount/frequency. |
| Limongelli L et al 2026 · study_type: observational | observational | supports | moderate | Retrospective study (n=248 children, Southern Italy) found a sugar-rich diet was associated with markedly increased ECC risk (OR=4.14, p<0.001), alongside night-time feeding duration and oral hygiene factors. |
| Sava-Rosianu R et al 2026 · study_type: observational | observational | tested-null | low | Cross-sectional geographic analysis (n=391 Romanian preschoolers) found spatial variation in sugar intake by county but adjusted R2 for geography was modest (0.04-0.07); does not directly test sugar-caries association at individual level. |
| Rios A et al 2026 · study_type: RCT | RCT | tested-null | low | RCT (n=100) using Stephan's curve nutrition counseling reduced added sugar intake by 50.8% vs 5.2% control (p=0.001); study did not report caries/DMFT outcome changes over the short 2-week follow-up, only intake behavior. |
| Compagnoni F et al 2026 · study_type: mechanism | observational | supports | low | Historical review of Mantegazza's 1864 laboratory experiments concluding sugar has no direct chemical action on enamel but causes caries via fermentation processes, anticipating the modern microbiological explanation. |
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