Elawady: the harm of soda is the carbonated water itself, not the sugar or sweetener; one 300 ml Pepsi delivers more carbon dioxide than the body produces in a whole day, and colas contain sodium bicarbonate that neutralises stomach acid and increases reflux.
Original statement
انت عارفكوبايه اللي هو البيبسي ال 300 ملي دول يكفوك يعملوا فيك قد ايه ثاني اكسيد الكربون اكت من اللي انت بتنتجه في جسمك على مدار اليوم ... حموضه الكوكا كولا وال والمياه الغازيه هي بتوصل 2.3 من قريبه من حموضه المعده بلس ان انا حاطط فيها صوديوم بايكربونيت
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
Elawady: the harm of soda is the carbonated water itself, not the sugar or sweetener; one 300 ml Pepsi delivers more carbon dioxide than the body produces in a whole day, and colas contain sodium bicarbonate that neutralises stomach acid and increases reflux.
Origin
- Source status
- Video transcript (own words)
- Attribution
- Elawady (machine transcript)
- Video
- Dr Diaa Al Awady د ضياء العوضي is live! لايف هزار (Open source)
- Published
- 1 September 2025
- Timestamp
- not available (transcript has no timings)
- Attribution uncertainty
- Machine/CC transcript; wording may contain transcription errors.
- Claimed mechanism
Carbon dioxide load; sodium bicarbonate neutralising gastric acid.
- Claimed health effect
Disturbed digestion, reflux.
- Population concerned
Everyone
- 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/CC transcript; wording may contain transcription errors.
- Source status
- Video transcript (own words)
- Attribution
- Elawady (machine transcript)
- Video
- ايه اللى بيحصل فى معدتنا بعد اكل العيش .. فيديو خطير وكلام اول مرة تسمعوه (Open source)
- Published
- 24 March 2021
- Timestamp
- not available (transcript has no timings)
- Attribution uncertainty
- Machine transcript (2021 video); attribution assumed from archive listing.
Scientific assessment
False – The statement contradicts the robust evidence.
Certainty of evidence: high – Further research is very unlikely to change the assessment.
1. What was claimed?
Carbonation, not sugar, is the problem; one can of Pepsi exceeds daily body CO2 production; colas contain bicarbonate that neutralises stomach acid.
2. What is demonstrably correct?
Colas are acidic. Sodium bicarbonate does neutralise stomach acid and produces CO2 (relevant for effervescent antacids, which he also mentions).
3. What is wrong or exaggerated?
The CO2 comparison is wrong by a factor of several hundred: a 300 mL soda contains about 1.8 g of carbon dioxide, while the body produces about 1 kg per day and exhales it continuously; the CO2 in one soda equals about 2-3 minutes of the body's own production. Colas are strongly acidic (Pepsi pH 2.39), not alkaline, and are not formulated as antacids; an acidic drink cannot neutralise gastric acid. Carbonation did not alter the blood-sugar response to a sweet drink in a controlled study. Saying the sugar is irrelevant contradicts the archive's own case, which rests mostly on sugar-related evidence (C-SOD-01 to C-SOD-05).
4. What remains unclear?
None material.
5. Which studies support it?
None.
6. Which studies contradict it?
I-SOD-114 (measured cola pH), I-SOD-115 (CO2 content of soft drinks), I-SOD-116 (daily human CO2 output), I-SOD-117 (carbonation does not change glycaemic response); A-SOD-03 (colas contain phosphoric acid); I-SOD-01.
7. What applies to Germany and Europe?
Not region-specific.
8. What is known about Egypt?
Not region-specific.
9. What practical conclusion is appropriate?
The main established health concern with regular soda is its sugar (and acid for teeth), not the carbon dioxide.
Assessment details
- Rationale for certainty of evidence
Quantified with fetched sources: carbonated soft drinks contain about 6 g CO2 per litre (I-SOD-115), i.e. about 1.8 g in 300 mL, while one person produces about 1 kg CO2 per day (I-SOD-116), roughly 550 times more (stats/C-SOD-13_co2_budget.py). Measured pH of Pepsi is 2.39 and of Coca-Cola 2.37 (I-SOD-114), incompatible with bicarbonate neutralisation of stomach acid. In a human crossover study, carbonation did not change the glycaemic response, gastric emptying or satiety of a sugary drink (I-SOD-117). The sugar-related harms are documented in C-SOD-01 to C-SOD-05.
- Source quality
Own words (machine transcript). Internally inconsistent: in the same remarks he says colas are about as acidic as the stomach (pH ~2.3) and that they neutralise stomach acid.
- Regional transferability
Universal.
- Individual exceptions
None.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 26 October 2026 provisional
Scientific evidence in detail
Scientifically refuted – High-quality evidence shows the opposite, or the claim contradicts well-established physiology.
Research question: Is the harm of soda caused by its carbon dioxide rather than its sugar; does a 300 mL Pepsi deliver more CO2 than the body produces in a day; and do colas contain bicarbonate that neutralises stomach acid?
Research question in detail (PECO)
- Population
- General population
- Intervention or exposure
- Carbonation (dissolved CO2) and cola ingredients
- Comparison
- Non-carbonated drinks; body CO2 production
- Geographic scope
- universal chemistry and physiology
- Outcomes
- CO2 dose vs metabolic CO2 production
- Beverage pH
- Glycaemic and gastric response to carbonation
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
No high-quality evidence supporting the claim was found.
What speaks against the claim?
A person breathes out about 1 kg of CO2 a day
O'Sullivan C et al.. NPJ Microgravity 2026 · PMID 42120392 · DOI 10.1038/s41526-026-00608-x Narrative reviewabstract checkednewly addedSpace life-support engineering uses about 1 kg of CO2 per crew member per day.
- Actual result
- 'one crew member, i.e., 1 kg per day'.
- Methodological quality
- moderate (indirect but standard design value)
- Relevance
- direct for the quantity
- Limitations
- Approximate.
A soft drink holds about 6 g of CO2 per litre
Kuntzleman TS, Kuntzleman JT. Molecules 2021 · PMID 33802982 · DOI 10.3390/molecules26061691 Otherabstract checkednewly addedCarbonated soft drinks contain about 6 g CO2 per litre, i.e. about 1.8 g in 300 mL.
- Actual result
- ~6.0 g CO2 per litre.
- Methodological quality
- moderate
- Relevance
- direct for the quantity
- Limitations
- Approximate, not brand-specific.
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 addedMeasured pH of Pepsi 2.39 and Coca-Cola 2.37: strongly acidic, inconsistent with bicarbonate buffering.
- Actual result
- Pepsi 2.39 +- 0.03; Coca-Cola Classic 2.37 +- 0.03.
- Methodological quality
- high (direct measurement)
- Relevance
- direct
- Limitations
- US products.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
The body produces roughly 550 times more CO2 per day than one 300 mL soda contains; colas are strongly acidic and do not neutralise stomach acid; carbonation did not change the glycaemic response to a sugary drink. The established harms of soda are linked to its sugar (and acidity for teeth).
Why some studies weigh more
Physical measurements and standard physiology outweigh the absence of any supporting human data.
Is a causal relationship established? Not applicable Factual/chemical claims.
Remaining uncertainty
Brand-specific CO2 content; Egyptian formulations not measured.
Justified conclusion
This claim is false.
Why do studies seem to disagree?
A rat study (not added; PMID 28228348) proposed CO2-induced ghrelin release; no human confirmation was found, and a human trial (I-SOD-117) found no effect of carbonation on glycaemia or satiety.
Does this depend on the country?
- General biological effects
- Universal.
A regional difference that changes the conclusion is not supported by robust data.
Statistical re-check
- CO2 in 300 mL soda vs daily body production – 1.8 g vs ~1000 g/day = 0.18% (body produces ~556 times more); strong carbonated water 2.6 g (0.26%); one soda equals ~2.6 minutes of metabolic CO2 recalculated
- Acidity of cola vs sparkling water – Pepsi has ~720 times the hydrogen-ion concentration of Perrier recalculated
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- CO2 dose comparison and cola acidity
- Starting level
- high (randomised trials)
- Result
- high
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.
Search strategy
Documented literature searches for this review (search strings in the original database syntax).
| Database | Date | Search | Looking for | Hits | Included |
|---|---|---|---|---|---|
| PubMed | 26 October 2026 | (carbon dioxide[ti] OR carbonation[ti]) AND (beverage*[ti] OR drink*[ti]) AND (stomach[tiab] OR gastric[tiab] OR esophag*[tiab]) | supporting evidence | 3 | |
| Europe PMC | 26 October 2026 | ("carbonated beverages" OR "carbonated drinks" OR "carbonation") AND ("carbon dioxide") AND (harmful OR adverse OR ghrelin OR "gastric distension" OR bloating) AND (human OR humans OR volunteers) | supporting evidence | 546 | |
| Europe PMC | 26 October 2026 | ("carbon dioxide production" OR "CO2 production" OR VCO2) AND (resting OR rest) AND ("ml/min" OR "mL/min") AND (healthy adults) AND (indirect calorimetry) AND (reference OR normal values) | contradicting evidence | 285 | |
| Europe PMC | 26 October 2026 | ("carbon dioxide" OR CO2) AND ("per day" OR "daily") AND ("human body" OR "humans" OR "adult") AND ("200 mL/min" OR "200 ml/min" OR "1 kg" OR "approximately 1 kg") AND (production OR exhaled OR excreted) | contradicting evidence | 2397 | |
| Europe PMC | 26 October 2026 | (cola OR "soft drink" OR "carbonated beverage") AND ("CO2 content" OR "carbon dioxide content" OR "dissolved CO2" OR "carbonation level") AND ("g/L" OR "g L" OR "volumes") | contradicting evidence | 23 | |
| PubMed | 26 October 2026 | Reddy A[au] AND pH of beverages[ti] | contradicting evidence | 1 |
Open questions
Measured CO2 content and ingredient lists of colas sold in Egypt.
How deeply was this checked?
6 linked studies: 0 checked in full text (0 of them with a structured risk-of-bias assessment), 6 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
History of the verdict
- 25 October 2026 · Phase 1 · Initial assessment: False (moderate)
- 26 October 2026 · Phase 4 (systematic evidence review) · Verdict changed: False (moderate) → False (high)
Certainty raised because the previously unquantified physiology is now documented with fetched sources (CO2 content, daily CO2 output, measured cola pH) and a human trial isolating carbonation.
New sources: I-SOD-114 I-SOD-115 I-SOD-116 I-SOD-117
In plain language
Dr. Diaa said that the gas in fizzy drinks, not the sugar, is the main problem, and that one glass contains more carbon dioxide than the body makes in a day. In reality, a 300 mL soda contains less than 2 grams of carbon dioxide, while the body makes about 1 kilogram every day and breathes it out. Colas are strongly acidic, so they cannot neutralise stomach acid. The best-documented harm of regular soda comes from its sugar.
Studies on this claim
Studies supporting the claim (0)
No studies in this group.
Studies contradicting or limiting the claim (6)
-
Cola and bone density in older women
Tucker KL et al.. Am J Clin Nutr 2006 · PMID 17023723 · DOI 10.1093/ajcn/84.4.936Cross-sectional studycited by the Tayebat archiveabstract checked★ key studyWomen drinking cola daily had 3.7% lower hip bone density; other fizzy drinks showed no link.
Does the study support the specific claim? Partly · 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?
Is cola consumption associated with lower BMD?
- How was the study done?
Cross-sectional analysis of BMD (DXA) by FFQ soft-drink frequency, Framingham Osteoporosis Study.
- How many people, animals or samples were studied?
1,413 women; 1,125 men; Older women and men
- What was actually found?
Women: cola associated with lower BMD at each hip site (P<0.001-0.05) but not spine; daily intake 3.7% lower femoral neck and 5.4% lower Ward's area BMD; similar for diet cola; no association in men or for non-cola carbonated beverages; phosphorus intake not significantly higher in daily cola drinkers.
- How large was the observed effect?
-3.7% femoral neck BMD (daily vs <1/month)
- What do the results mean in everyday life?
Possible small effect on bone in women; not shown for other fizzy drinks.
- What are the study's limitations?
Cross-sectional; Effect only in women and at hip; Mechanism not demonstrated (phosphorus intake similar); Self-reported intake
- What does it say about Elawady's specific claim?
Main evidence for C-SOD-08; also limits C-SOD-14 (no association for non-cola carbonated drinks).
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
That phosphoric acid causes bone loss or fractures.
-
Fizzy drinks and reflux: systematic review
Johnson T et al.. Aliment Pharmacol Ther 2010 · PMID 20055784 · DOI 10.1111/j.1365-2036.2010.04232.xSystematic reviewindependent cross-checkabstract checked★ key studyFizzy drinks briefly lower acidity in the food pipe, but there is no direct evidence that they cause reflux disease.
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?
Do carbonated beverages affect oesophageal pH, motility, damage, GERD symptoms and complications?
- How was the study done?
Systematic review (qualitative).
- How many people, animals or samples were studied?
Not stated in abstract; Not stated in abstract
- What was actually found?
Very short decline in intra-oesophageal pH; possible transient reduction of LES basal pressure; no evidence of direct oesophageal damage; not consistently shown to cause GERD symptoms; no evidence of GERD complications or oesophageal cancer.
- How large was the observed effect?
Not pooled
- What do the results mean in everyday life?
Fizzy drinks are not a proven cause of reflux disease.
- What are the study's limitations?
Old (2010); Limited primary evidence; No meta-analysis
- 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?
That nobody gets symptoms from them.
-
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.
Pepsi pH 2.39: acidic, not bicarbonate-buffered.
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.
-
A soft drink holds about 6 g of CO2 per litre
Kuntzleman TS, Kuntzleman JT. Molecules 2021 · PMID 33802982 · DOI 10.3390/molecules26061691Otherindependent cross-checkabstract checkedChemistry research states that carbonated soft drinks generally contain about 6 g of carbon dioxide per litre.
Soft drinks contain ~6 g CO2 per litre (~1.8 g per 300 mL).
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?
Study how bubbles form in soft drinks.
- How was the study done?
Laboratory experiments.
- How many people, animals or samples were studied?
Not applicable.
- What was actually found?
States typical CO2 content of soft drinks (~6 g/L).
- How large was the observed effect?
Not applicable.
- What do the results mean in everyday life?
A 300 mL drink holds less than 2 g of CO2.
- What are the study's limitations?
Approximate value.
- What does it say about Elawady's specific claim?
Shows the CO2 in a drink is tiny compared with what the body produces.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Not a health study.
-
A person breathes out about 1 kg of CO2 a day
O'Sullivan C et al.. NPJ Microgravity 2026 · PMID 42120392 · DOI 10.1038/s41526-026-00608-xNarrative reviewindependent cross-checkabstract checkedSpace life-support engineering uses about 1 kg of carbon dioxide per crew member per day as the design value.
One person produces ~1 kg CO2 per day.
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?
Review CO2 removal in spacecraft.
- How was the study done?
Technical review.
- How many people, animals or samples were studied?
Not applicable.
- What was actually found?
Each person produces about 1 kg of CO2 per day.
- How large was the observed effect?
Not applicable.
- What do the results mean in everyday life?
The body makes hundreds of times more CO2 each day than a can of soda contains.
- What are the study's limitations?
Indirect source.
- What does it say about Elawady's specific claim?
Refutes the CO2 comparison in the claim.
- Do the results apply to Germany and Europe?
Universal.
- What can explicitly not be concluded from this study?
Not a nutrition study.
-
Fizz does not change the blood-sugar effect of a sweet drink
Lau ERL, Henry CJ. Nutrition 2017 · PMID 28606564 · DOI 10.1016/j.nut.2017.02.001Randomised controlled trialindependent cross-checkabstract checkedAdding carbonation to a sugary drink did not change blood sugar, stomach emptying or fullness in 15 healthy adults.
Carbonation did not alter glycaemic response or gastric emptying.
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?
Test whether carbonation changes how a sugary drink is handled.
- How was the study done?
Same drink with different carbonation levels on different days.
- How many people, animals or samples were studied?
15 healthy adults.
- What was actually found?
No difference in blood sugar or stomach emptying.
- How large was the observed effect?
No significant differences.
- What do the results mean in everyday life?
The sugar, not the bubbles, drives the blood-sugar response.
- What are the study's limitations?
Very small, single tests.
- What does it say about Elawady's specific claim?
Contradicts 'the gas, not the sugar, is the problem'.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Cannot exclude subtle long-term effects.
No study in this group is marked as key.
Studies with mixed or unclear results (0)
No studies in this group.
Regional context
Germany / EU
Not region-specific.
Egypt
Not region-specific.
What applies in my country?
General scientific assessment
False This claim is false: one soda contains about 2 g of carbon dioxide versus about 1 kg produced by the body each day, colas are acidic rather than antacid, and sugar is the established problem.
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
- Colas, but not other carbonated beverages, are associated with low bone mineral density in older women: The Framingham Osteoporosis Study.. Tucker KL et al.. Am J Clin Nutr 2006 · PMID 17023723 · DOI 10.1093/ajcn/84.4.936
- Systematic review: the effects of carbonated beverages on gastro-oesophageal reflux disease.. Johnson T et al.. Aliment Pharmacol Ther 2010 · PMID 20055784 · DOI 10.1111/j.1365-2036.2010.04232.x
- 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
- Ethanol as a Probe for the Mechanism of Bubble Nucleation in the Diet Coke and Mentos Experiment.. Kuntzleman TS, Kuntzleman JT. Molecules 2021 · PMID 33802982 · DOI 10.3390/molecules26061691
- Review of carbon dioxide removal and recycling in space.. O'Sullivan C et al.. NPJ Microgravity 2026 · PMID 42120392 · DOI 10.1038/s41526-026-00608-x
- No influence of carbonation on glycemic response, gastric emptying, and satiety of sweetened drinks.. Lau ERL, Henry CJ. Nutrition 2017 · PMID 28606564 · DOI 10.1016/j.nut.2017.02.001