Sweeteners
added sugar causes dental caries
Strong support Sweeteners 🔬 Includes disconfirming
Part of: • Added sugar
RefutedContestedStrong support
consensus score 0.85
📅 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
9 support 0 contradict 4 tested null 0 mixed · 13 sources, 9 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, Wu J, Tian Z, Kim YW, Lim S, Choi SG, Park H, Kang JW, Choi JY, Kim DW 2025 · Medicine | 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 · BMC oral health | 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 PJ, Kelly SA 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, Ladeira LLC, de Oliveira ICV, de Queiroz LJ, Santos CC, Alves CMC, Thomaz EBAF, Ribeiro CCC 2026 · Clinical oral investigations | 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, Inchingolo AD, Muntean A, Bordea IR, Băbțan AM, Bondor CI, Tăulescu M, Roman G, Inceu G, Boșca AB, Inchingolo F, Ferrante L, Inchingolo AM, Salivages Project Group, Dipalma G, Manig F, Hellwig M, Henle T, Ilea A 2026 · Nutrients | 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, Tam KW, Mandeville KL, El-Saharty S, Hamza MM, Veerman JL 2026 · Public health in practice (Oxford, England) | 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, Shirato M, Shishido S, Lingström P 2026 · Scientific reports | 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 · Children (Basel, Switzerland) | 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 MJ, Waterhouse B, Aggarwal VR, Bloor K, Doran T 2021 · Eur J Public Health | meta-analysis | supports | moderate | SR/MA: sugar-sweetened beverage consumption associated with higher dental caries and erosion. |
| Enax J, Schulze Zur Wiesche E, Epple M 2026 · Dentistry journal | 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, O'Sullivan M, Winning L, Cassetti O, O'Sullivan A, Madigan S, Egan B, Crowe M 2026 · J Hum Nutr Diet | observational | tested-null | low | Cross-sectional study of 88 elite Irish athletes (84 in the cluster analysis); untreated caries (ICDAS >= 3) in 90%. The logistic model's outcome is membership of one of two CLARA clusters, not caries: cariogenic snack starch predicted membership (beta -0.044, p = 0.005), sugar variables did not (all p > 0.05), and the caries count was 'not significantly related to cluster assignment'. No estimate of sugar intake against dental caries is reported. |
| Schlueter N, Hellwig E, Geurtsen W, Rupf S 2026 · Clin Oral Investig | observational | supports | moderate | Clinical guideline, not evidence: 'This updated S3-guideline is intended to provide scientifically sound information on basic measures and recommendations for caries prevention'. Lists '(III) Reducing sugar consumption' as a recommendation; no new data. Review — zero weight. |
| More SG, Mistry LN, Patil A, Mishra H, Patil T, Jawdekar AM 2026 · Cureus | 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, Mathias FB, Schuch HS, Cenci MS, Correa MB, Huysmans MC, Demarco FF 2025 · Brazilian oral research | 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 P 2016 · Adv Nutr | observational | supports | moderate | Review: free sugars are the key modifiable dietary cause of caries; effect scales with amount/frequency. |
| Limongelli L, Granberg V, Cervinara F, Corsalini T, Di Venere D, Fricelli I, Corsalini M 2026 · Children (Basel, Switzerland) | 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, Campus GG, Alexa VT, Ilin A, Postolache M, Jumanca D, Oancea R, Sfeatcu R, Caramida M, Muntean A, Esian D, Murariu A, Daguci C, Balean O, Bolchis V, Buzatu BLR, Luca D, Toderas N, Galuscan A 2026 · Frontiers in oral health | 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, Perdomo A, Grainger C, Negrete C, Ko J, Oyoyo U, Kwon SR 2026 · Journal of education and health promotion | 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, Riva MA 2026 · British dental journal | 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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