Soft drinks cause tooth decay.
Original statement
حذَّر د. ضياء بشدة من المشروبات الغازية، واصفاً إيَّاها بأسوأ مشروب على الإطلاق، لمساهمتها في مشاكل الهضم، وارتجاع المريء، وتسوس الأسنان، ولتأثيرها السلبي على حمضية المعدة.
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
Soft drinks cause tooth decay.
Origin
- Source status
- Archive quote (no location given)
- Attribution
- Elawady (archive paraphrase; source video not given)
- Origin
- https://eltayebat.com/rule/soda/
- Attribution uncertainty
- The archive attributes this text to Dr. Diaa in its 'د. ضياء يقول' box but gives no video reference. Transcript check (the project's research files, keyword search of 307 archive transcripts): not_found. Tooth decay was not found in connection with soft drinks in the transcripts. Other parts of the same archive quote are found: 'worst drink ever invented' almost verbatim (E8MVNdW9_00, existing alt source) and reflux in connection with Pepsi indirectly (PBygUgVhUM8). The tooth-decay element may be the archive's own addition.
- Claimed mechanism
Sugars and acids (Elawady additionally attributes decay to reflux).
- Claimed health effect
Dental caries and erosion.
- Population concerned
Children and adults
- Geographic restriction by Elawady
none found
Diverging source versions
- Source status
- Video transcript (own words)
- Attribution
- Elawady (machine transcript)
- Video
- الجن . آلام العمود الفقري . الحقيقه والسراب (Open source)
- Published
- 26 November 2025
- Timestamp
- not available (transcript has no timings)
- Attribution uncertainty
- Machine transcript; in this programme a TV report with other speakers is interleaved, so attribution of individual sentences is uncertain.
Scientific assessment
True – The statement is supported by robust evidence.
Certainty of evidence: moderate – Further research may still affect the assessment.
1. What was claimed?
Sodas rot teeth.
2. What is demonstrably correct?
Valenzuela 2021 (A-SOD-19): caries OR 1.57 (1.28-1.92) moderate vs low consumption and erosion OR 3.09 (1.37-6.97) high vs moderate; Moores 2022 (I-SUG-04): caries lower when sugars <10% energy (moderate-quality evidence).
3. What is wrong or exaggerated?
Elawady attributes decay mainly to reflux in his transcript; the established mechanisms are bacterial fermentation of sugars and direct acid erosion. The same sugar-caries mechanism applies to honey, jam, sweets and juices allowed in the system.
4. What remains unclear?
Relative contribution of diet sodas (acid erosion without sugar).
5. Which studies support it?
I-SUG-03 (causal hazard), I-SUG-04, I-SUG-05; A-SOD-19 (magnitude, cross-sectional, low certainty).
6. Which studies contradict it?
None.
7. What applies to Germany and Europe?
WHO free sugars guideline applies.
8. What is known about Egypt?
No Egypt-specific data.
9. What practical conclusion is appropriate?
Limit sugary and acidic drinks; good oral hygiene.
Assessment details
- Rationale for certainty of evidence
The causal sugar-caries relationship is well established (EFSA 2022, I-SUG-03: 'well-established hazard'; WHO sugar guideline based on moderate-quality evidence); acidity explains erosion. The archive's cited systematic review (A-SOD-19) includes only cross-sectional studies with unadjusted pooled estimates and heterogeneity up to I2 ~98%; its own 'high certainty' GRADE rating starts observational evidence at high, contrary to standard GRADE, so it is used for magnitude only, with low certainty.
- Source quality
Archive cites an appropriate systematic review.
- Regional transferability
High.
- Individual exceptions
Fluoride exposure and oral hygiene modify risk.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 26 October 2026 provisional
Scientific evidence in detail
Scientifically well supported – The claim agrees with consistent, high-quality evidence.
Research question: Do soft drinks cause tooth decay and erosion?
Research question in detail (PECO)
- Population
- Children and adults
- Intervention or exposure
- Soft drinks (sugar and acid)
- Comparison
- Low or no intake
- Geographic scope
- universal; very common in Egyptian children
- Outcomes
- Caries
- Dental erosion
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
EFSA: how much sugar is safe?
EFSA NDA Panel et al.. EFSA J 2022 · PMID 35251356 · DOI 10.2903/j.efsa.2022.7074 Risk assessmentfull text, structured risk-of-bias assessmentEFSA 2022: dietary sugars are a well-established hazard for dental caries.
- Actual result
- Well-established hazard.
- Methodological quality
- high
- Relevance
- direct
- Limitations
- Agency assessment.
Sugar and tooth decay: 10-year update
Moores CJ et al.. J Dent Res 2022 · PMID 35302414 · DOI 10.1177/00220345221082918 Systematic reviewabstract checkedSystematic review (78 studies): 64 showed at least one positive sugar-caries association; caries lower below 10% energy.
- Actual result
- Moderate-quality evidence for <10%E.
- Methodological quality
- moderate
- Relevance
- direct
- Limitations
- Observational.
Colas are strongly acidic; sparkling water is not
Reddy A et al.. J Am Dent Assoc 2016 · PMID 26653863 · DOI 10.1016/j.adaj.2015.10.019 Measurement / residue studyabstract checkednewly addedMost soft drinks are erosive (pH <4); colas pH ~2.4.
- Actual result
- 93% of 379 beverages pH <4.0.
- Methodological quality
- moderate
- Relevance
- direct for erosion potential
- Limitations
- Laboratory pH only.
What speaks against the claim?
No high-quality evidence against the claim was found.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
Correct: sugar causes caries and acidity causes erosion.
Why some studies weigh more
Agency assessments and systematic reviews.
Is a causal relationship established? Yes, established Bacterial fermentation of sugars and acid dissolution of enamel.
Remaining uncertainty
None material.
Justified conclusion
True.
Does this depend on the country?
- General biological effects
- Universal.
- Eating habits
- Egyptian study: 84% of children aged 2-6 drank sugary drinks daily; 81% had caries.
A regional difference that changes the conclusion is not supported by robust data.
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- Caries with free sugars
- Starting level
- low (observational studies)
- Reasons for upgrading
- dose-response
- established mechanism
- Result
- moderate
Simplified assessment by a single reviewer, following the GRADE approach; not a formal GRADE panel. GRADE rates the body of evidence for one outcome, not individual studies.
Clinical guidelines and official statements checked
- WHO: Guideline: sugars intake for adults and children (2015), publication page and news release (I-SUG-05) (2015) · Original publication
Reduce free sugars to <10% of energy (strong); further reduction to <5% (~25 g) conditional. Free sugars include sugars added by manufacturer, cook or consumer and sugars naturally present in honey, syrups, fruit juices and concentrates (news release https://www.who.int/news/item/04-03-2015-who-calls-on-countries-to-reduce-sugars-intake-among-adults-and-children, fetched 2026-10-26).
Search strategy
Documented literature searches for this review (search strings in the original database syntax).
| Database | Date | Search | Looking for | Hits | Included |
|---|---|---|---|---|---|
| Europe PMC | 26 October 2026 | ("soft drinks" OR "sugar-sweetened beverages") AND (caries OR "dental erosion") AND ("no association" OR "not associated" OR "no significant association") | contradicting evidence | 2852 | |
| Europe PMC | 26 October 2026 | (Egypt OR Egyptian) AND ("sugar-sweetened beverages" OR "soft drinks" OR "carbonated beverages" OR "added sugar") AND (obesity OR diabetes OR caries OR intake) | supporting evidence | 1302 | |
| PubMed | 26 October 2026 | Reddy A[au] AND pH of beverages[ti] | supporting evidence | 1 |
Open questions
None.
How deeply was this checked?
6 linked studies: 3 checked in full text (2 of them with a structured risk-of-bias assessment), 3 on the basis of the abstract, 0 bibliographically only. No formal assessment with two independent reviewers and no independent human expert review has taken place yet.
Last scientific review: 26 October 2026
In plain language
Drinking sugary soft drinks is clearly linked to more tooth decay and tooth erosion. Bacteria in the mouth turn sugar into acid, and the drinks are acidic themselves. This applies to all sources of free sugar, including honey, jam, sweets and juice.
Studies on this claim
Studies supporting the claim (6)
-
Sugary drinks and teeth
Valenzuela MJ et al.. Eur J Public Health 2021 · PMID 32830237 · DOI 10.1093/eurpub/ckaa147Meta-analysiscited by the Tayebat archivefull text, structured risk-of-bias assessmentMore sugary drinks were linked with more tooth decay and erosion, increasing with amount.
Does the study support the specific claim? Yes · Methodological quality: low · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Is SSB consumption associated with caries and erosion?
- How was the study done?
Systematic review and meta-analysis of cross-sectional studies with GRADE.
- How many people, animals or samples were studied?
38 cross-sectional studies; Children and adults
- What was actually found?
Moderate vs low: caries OR 1.57 (1.28-1.92), DMFT WMD 0.82; erosion OR 1.43 (1.01-2.03). High vs moderate: caries OR 1.53 (1.17-1.99), erosion OR 3.09 (1.37-6.97). Dose-response; high certainty for caries (authors).
- How large was the observed effect?
Caries OR 1.57; erosion OR 3.09
- What do the results mean in everyday life?
Sugary drinks damage teeth.
- What are the study's limitations?
Almost all included studies were cross-sectional and the pooled data were not adjusted for income or fluoride; results varied a lot between studies; the authors' 'high certainty' rating is generous.
- What does it say about Elawady's specific claim?
Supports C-SOD-11.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
It cannot by itself prove cause and effect or give a precise size of the effect; it does not separate the effect of sugar from the effect of acidity.
-
Sugar and tooth decay: 10-year update
Moores CJ et al.. J Dent Res 2022 · PMID 35302414 · DOI 10.1177/00220345221082918Systematic reviewindependent cross-checkabstract checkedMost studies link more sugar with more tooth decay; keeping sugar below 10% of energy lowers decay.
Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Association of sugars amount with caries; effect of <10% and <5% energy.
- How was the study done?
Systematic review update (2011-2020) with GRADE.
- How many people, animals or samples were studied?
23 new studies; 78 total; Children and adults
- What was actually found?
64 of 78 studies showed at least one positive association; caries lower when sugars <10%E (moderate quality); <5%E evidence upgraded to low.
- How large was the observed effect?
Not pooled
- What do the results mean in everyday life?
All free sugars affect teeth.
- What are the study's limitations?
Vote counting; Mostly observational
- What does it say about Elawady's specific claim?
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Not applicable.
-
WHO sugar guideline
World Health Organization. WHO news release 2015Guideline / position statementindependent cross-checkfull text checked★ key studyWHO recommends keeping free sugars, including honey and juice sugars, below 10% of energy.
Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Recommended limit for free sugars.
- How was the study done?
International guideline (news release read in full).
- How many people, animals or samples were studied?
Not applicable; Adults and children
- What was actually found?
Free sugars <10% of total energy (strong recommendation); further reduction <5% (~25 g, 6 teaspoons) conditional. Free sugars include sugars added by manufacturer, cook or consumer and sugars naturally present in honey, syrups, fruit juices and fruit juice concentrates; not sugars in fresh fruit, vegetables or milk. A can of sugar-sweetened soda contains up to 40 g free sugars.
- How large was the observed effect?
<10% energy (strong); <5% (conditional)
- What do the results mean in everyday life?
Honey, juices and table sugar all count.
- What are the study's limitations?
Conditional recommendation for <5%
- What does it say about Elawady's specific claim?
Defines honey and juices as free sugars: contradicts C-SUG-01 and C-SUG-06; supports C-SUG-02.
- Do the results apply to Germany and Europe?
Applies globally including EU and Egypt.
- What can explicitly not be concluded from this study?
Not applicable.
-
EFSA: how much sugar is safe?
EFSA NDA Panel et al.. EFSA J 2022 · PMID 35251356 · DOI 10.2903/j.efsa.2022.7074Risk assessmentindependent cross-checkfull text, structured risk-of-bias assessment★ key studyEFSA found no safe intake level and advises keeping added and free sugars as low as possible.
Does the study support the specific claim? No · Methodological quality: high · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Can a UL or safe level for dietary sugars be set?
- How was the study done?
Regulatory scientific opinion with systematic reviews.
- How many people, animals or samples were studied?
Not applicable; General population
- What was actually found?
Sugars are a well-established hazard for caries; RCTs on surrogate endpoints show causal positive relationship of added/free sugars with obesity and dyslipidaemia (moderate certainty), NAFLD and T2D (low), hypertension (very low); no safe level identified; intake of added and free sugars should be as low as possible in a nutritionally adequate diet.
- How large was the observed effect?
Not applicable
- What do the results mean in everyday life?
Applies to sugar, honey and syrups alike.
- What are the study's limitations?
Trials looked at markers (weight, liver fat, blood fats) rather than diseases; cohort studies mostly compared sugar with other calories at equal total energy; few data below 10% of energy.
- What does it say about Elawady's specific claim?
Contradicts C-SUG-01, C-SUG-05 (health relevance); supports C-SOD-01.
- Do the results apply to Germany and Europe?
Directly applicable in EU/Germany.
- What can explicitly not be concluded from this study?
It cannot name a safe daily amount of sugar; it does not show that sugar is harmful when it does not add extra calories, except for tooth decay.
-
Colas are strongly acidic; sparkling water is not
Reddy A et al.. J Am Dent Assoc 2016 · PMID 26653863 · DOI 10.1016/j.adaj.2015.10.019Measurement / residue studyindependent cross-checkabstract checked★ key studyMeasured pH: Pepsi 2.39 and Coca-Cola 2.37 (strongly acidic), plain sparkling mineral water 5.25.
Most soft drinks erosive (pH <4).
Does the study support the specific claim? No · Methodological quality: moderate · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Measure acidity of beverages.
- How was the study done?
Laboratory pH measurements.
- How many people, animals or samples were studied?
379 beverages.
- What was actually found?
Most drinks are acidic; colas among the most acidic; sparkling mineral water much less.
- How large was the observed effect?
Pepsi pH 2.39; Perrier 5.25.
- What do the results mean in everyday life?
Cola is acidic and erosive to teeth; it cannot neutralise stomach acid.
- What are the study's limitations?
pH alone does not determine erosion.
- What does it say about Elawady's specific claim?
Contradicts the bicarbonate claim; supports tooth-damage claim.
- Do the results apply to Germany and Europe?
Same brands sold in Europe and Egypt.
- What can explicitly not be concluded from this study?
Cannot measure effects inside the body.
-
Sugary drinks and tooth decay in Egyptian toddlers
Taha A et al.. Int J Paediatr Dent 2025 · PMID 40468570 · DOI 10.1111/ipd.13324Cross-sectional studyindependent cross-checkabstract checkedIn 412 Egyptian children aged 2-6, 84% drank sugary drinks daily and 81% had tooth decay; sugary drinks helped explain links between feeding styles and decay.
Egypt: 84% of young children drink sugary drinks daily; mediates caries.
Does the study support the specific claim? Yes · Methodological quality: low · Certainty of evidence: see overall assessment of the claim
Original publication · Scientific details
Study explained simply
- What did the researchers want to find out?
Study feeding styles, sugary drinks and caries in Egyptian children.
- How was the study done?
Cross-sectional study with dental examinations.
- How many people, animals or samples were studied?
412 children.
- What was actually found?
High caries and sugary-drink rates; drinks mediated part of the link.
- How large was the observed effect?
AOR 2.35 for instrumental feeding.
- What do the results mean in everyday life?
Limiting sugary drinks matters for children's teeth in Egypt.
- What are the study's limitations?
Cross-sectional; one hospital.
- What does it say about Elawady's specific claim?
Supports the claim in an Egyptian setting.
- Do the results apply to Germany and Europe?
Egypt-specific.
- What can explicitly not be concluded from this study?
Cannot prove causation.
No study in this group is marked as key.
Studies contradicting or limiting the claim (0)
No studies in this group.
Studies with mixed or unclear results (0)
No studies in this group.
Regional context
Germany / EU
WHO free sugars guideline applies.
Egypt
No Egypt-specific data.
What applies in my country?
General scientific assessment
True Correct: sugary and acidic soft drinks damage teeth.
The following areas of food safety are relevant to this statement:
- Additives and processing
Honey, sugar, sweets
Choose a country to see the checked information for it.
Limits: legal rules describe what is allowed, not what every single food contains. Measurement data come from samples and are meaningful only together with their method details.
Country of residence or purchase Compare with another country
References
- Effect of sugar-sweetened beverages on oral health: a systematic review and meta-analysis.. Valenzuela MJ et al.. Eur J Public Health 2021 · PMID 32830237 · DOI 10.1093/eurpub/ckaa147
- Systematic Review of the Effect on Caries of Sugars Intake: Ten-Year Update.. Moores CJ et al.. J Dent Res 2022 · PMID 35302414 · DOI 10.1177/00220345221082918
- WHO calls on countries to reduce sugars intake among adults and children (Guideline: Sugars intake for adults and children, 2015) — news release. World Health Organization. WHO news release 2015
- Tolerable upper intake level for dietary sugars.. EFSA NDA Panel et al.. EFSA J 2022 · PMID 35251356 · DOI 10.2903/j.efsa.2022.7074
- The pH of beverages in the United States.. Reddy A et al.. J Am Dent Assoc 2016 · PMID 26653863 · DOI 10.1016/j.adaj.2015.10.019
- Parental Feeding Styles, Sugary Drinks Intake, and Early Childhood Caries in Egyptian Children: A Mediation Analysis.. Taha A et al.. Int J Paediatr Dent 2025 · PMID 40468570 · DOI 10.1111/ipd.13324