Phosphoric acid in cola drains the bones; women who drink cola daily (sugary or diet) have 3.7% lower hip bone density.
Original statement
حمض فوسفوريك يستنزف العظام ... في دراسة عظام فرامنغهام عام 2006، النساء اللواتي يشربن كولا يومياً (سكرية أو دايت) كانت كثافة عنق عظم الفخذ لديهن أقل بنسبة 3.7%، رغم تعديل النتائج للعمر والكالسيوم وفيتامين د.
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
Phosphoric acid in cola drains the bones; women who drink cola daily (sugary or diet) have 3.7% lower hip bone density.
Origin
- Source status
- Archive editors
- Attribution
- Archive editors (study selection and narrative are the archive's, not necessarily Elawady's)
- Origin
- https://eltayebat.com/rule/soda/
- Attribution uncertainty
- The archive homepage states that the forbidden-food section is supported by research 'independently of Dr. Diaa's words'. No evidence was found that Elawady himself cited these studies.
- Claimed mechanism
Phosphoric acid lowers calcium-phosphorus ratio; displacement of milk.
- Claimed health effect
Lower bone mineral density, osteoporosis.
- Population concerned
Older women
- Geographic restriction by Elawady
none found
Scientific assessment
Potentially false – The available evidence tends to speak against the statement, but is not conclusive.
Certainty of evidence: low – Further research is likely to change the assessment considerably.
1. What was claimed?
Cola's phosphoric acid causes bone loss.
2. What is demonstrably correct?
Tucker 2006 (A-SOD-03) found 3.7% lower femoral-neck BMD in women drinking cola daily vs <1/month; similar for diet cola; the archive reports this correctly. Soda consumption is associated with lower bone density (I-SOD-07) and more hip fractures in women (I-SOD-123, RR 1.14 per daily serving).
3. What is wrong or exaggerated?
The explanation 'phosphoric acid drains the bones' is not supported: phosphoric acid without caffeine did not increase calcium loss in a controlled study (I-SOD-124), and in a large cohort colas were no worse than other sodas for hip fractures (I-SOD-123). In Tucker 2006 the association was found in women only, at hip sites but not the spine, and total phosphorus intake was not higher in daily cola drinkers. Displacement of milk and confounding are more likely explanations.
4. What remains unclear?
Whether cola causes fractures.
5. Which studies support it?
A-SOD-03, I-SOD-07 (association with BMD); I-SOD-123 (association with hip fracture, not cola-specific).
6. Which studies contradict it?
I-SOD-124 (no calciuric effect of phosphoric acid); I-SOD-123 (no cola-specific risk); A-SOD-03 itself (no association in men or for non-cola drinks).
7. What applies to Germany and Europe?
No EU regulatory concern about phosphoric acid at authorised levels was reviewed here.
8. What is known about Egypt?
No Egypt-specific data.
9. What practical conclusion is appropriate?
Not drinking soda daily is reasonable, but the specific claim that cola's phosphoric acid drains the bones is not supported.
Assessment details
- Rationale for certainty of evidence
The claimed mechanism was tested directly: in a randomised crossover study, phosphoric acid without caffeine did not increase urinary calcium (I-SOD-124). A cohort of 73,572 women found soda associated with hip fracture but with no difference between colas and non-colas (I-SOD-123). The cola-specific BMD finding (A-SOD-03) is cross-sectional, in women only, and the 2021 meta-analysis (I-SOD-07) concerns SSB generally. Certainty is low because long-term mechanistic data are lacking.
- Source quality
Numbers correct; 'drains bone' is a causal mechanism not shown by the study.
- Regional transferability
Moderate.
- Individual exceptions
Not applicable.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 26 October 2026 provisional
Scientific evidence in detail
Overinterpreted – A real finding exists, but the claim draws more from it than the data allow (e.g. association taken as cause, animal data applied to humans, small effect presented as large).
Research question: Does phosphoric acid in cola cause bone loss, and do women drinking cola daily have lower hip bone density?
Research question in detail (PECO)
- Population
- Adults, especially women
- Intervention or exposure
- Cola (phosphoric acid)
- Comparison
- Non-cola carbonated drinks; low intake
- Geographic scope
- universal
- Outcomes
- Bone mineral density
- Hip fracture
- Urinary calcium
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
Cola and bone density in older women
Tucker KL et al.. Am J Clin Nutr 2006 · PMID 17023723 · DOI 10.1093/ajcn/84.4.936 Cross-sectional studyabstract checkedTucker 2006: daily cola associated with 3.7% lower femoral-neck BMD in women; not in men or for non-cola drinks.
- Actual result
- 3.7% lower femoral-neck BMD.
- Methodological quality
- moderate (cross-sectional)
- Relevance
- direct
- Limitations
- Cross-sectional; women only.
Soda linked to more hip fractures, cola or not
Fung TT et al.. Am J Clin Nutr 2014 · PMID 25099544 · DOI 10.3945/ajcn.114.083352 Cohort studyabstract checkednewly addedFung 2014 (73,572 women): each daily soda associated with 14% more hip fractures.
- Actual result
- RR 1.14 (1.06-1.23); colas and non-colas similar.
- Methodological quality
- high (cohort)
- Relevance
- indirect for the phosphoric-acid mechanism
- Limitations
- Observational.
What speaks against the claim?
Phosphoric acid in cola did not increase calcium loss
Heaney RP, Rafferty K. Am J Clin Nutr 2001 · PMID 11522558 · DOI 10.1093/ajcn/74.3.343 Randomised controlled trialabstract checkednewly addedHeaney 2001 RCT: phosphoric acid without caffeine did not increase urinary calcium; only caffeine did, slightly.
- Actual result
- Excess calciuria ~0.25 mmol with caffeinated drinks only.
- Methodological quality
- moderate (acute RCT)
- Relevance
- direct for mechanism
- Limitations
- Acute endpoint.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
Soda (cola and non-cola) is associated with lower bone density and more hip fractures in women, but the phosphoric-acid mechanism is not supported; milk displacement and confounding are more likely explanations.
Why some studies weigh more
Direct mechanistic RCT and a large cohort without cola specificity outweigh the cross-sectional cola-specific finding.
Is a causal relationship established? Not established Association without a demonstrated mechanism.
Remaining uncertainty
Causality of the association.
Justified conclusion
The archive's figure is correct; the explanation is not.
Why do studies seem to disagree?
Tucker (cola-specific) vs Fung (no cola vs non-cola difference): cross-sectional BMD versus prospective fractures; different populations.
Does this depend on the country?
- General biological effects
- Universal.
- Eating habits
- Milk displacement depends on local diet.
A regional difference that changes the conclusion is not supported by robust data.
Statistical re-check
- Log-symmetry; crude cumulative incidence – RR 1.14 symmetric; 2.5% hip fractures over up to 30 years recalculated
- Size of caffeine-related calciuria – ~0.25 mmol = ~10 mg calcium per test session recalculated
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- Bone loss caused by phosphoric acid in cola
- Starting level
- low (observational studies)
- Reasons for downgrading
- inconsistency
- indirectness
- Result
- low
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 | (soda[ti] OR cola[ti] OR soft drink*[ti] OR carbonated[ti]) AND (fracture*[ti] OR bone[ti] OR calcium[ti]) | both directions | 131 | |
| PubMed | 26 October 2026 | Fung TT[au] AND soda AND hip fracture | supporting evidence | 1 | |
| PubMed | 26 October 2026 | Heaney RP[au] AND carbonated beverages AND urinary calcium | contradicting evidence | 2 |
Open questions
Long-term effects of phosphoric acid intake.
How deeply was this checked?
4 linked studies: 0 checked in full text (0 of them with a structured risk-of-bias assessment), 4 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: Unclear / insufficient evidence (low)
- 26 October 2026 · Phase 4 (systematic evidence review) · Verdict changed: Unclear / insufficient evidence (low) → Potentially false (low)
Changed because direct evidence on the claimed mechanism was found: an RCT showed no calciuric effect of phosphoric acid, and a large cohort showed no cola-specific fracture risk. The association between soda and bone remains, but the claim attributes it to phosphoric acid.
New sources: I-SOD-123 I-SOD-124
In plain language
Women who drank cola daily had slightly lower hip bone density in one US study, and a large study of nurses found more hip fractures among women who drank more soda. But colas were no worse than other sodas, and a controlled test found that the acid in cola did not make the body lose calcium. So soda may be a marker of other habits, such as drinking less milk, rather than the acid itself harming bones.
Studies on this claim
Studies supporting the claim (1)
-
Sugary drinks and bone density: meta-analysis
Ahn H, Park YK. Nutr J 2021 · PMID 33952276 · DOI 10.1186/s12937-021-00698-1Meta-analysisindependent cross-checkabstract checkedHigher sugary and fizzy drink intake was linked with lower bone density in adults.
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 SSB consumption associated with bone health?
- How was the study done?
Systematic review and meta-analysis (mainly observational).
- How many people, animals or samples were studied?
26 publications; 124,691 participants (meta-analysis n=4,312); Children and adults
- What was actually found?
Adults: ES -0.66 (-1.01 to -0.31); carbonated beverages ES -0.73 (-1.12 to -0.35); 18 of 20 qualitative studies supportive.
- How large was the observed effect?
ES -0.66
- What do the results mean in everyday life?
Association only.
- What are the study's limitations?
Observational; Small meta-analysed sample; Large SMDs suggest heterogeneity
- What does it say about Elawady's specific claim?
Supports direction of C-SOD-08 (not mechanism).
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
That phosphoric acid causes bone loss.
No study in this group is marked as key.
Studies contradicting or limiting the claim (1)
-
Phosphoric acid in cola did not increase calcium loss
Heaney RP, Rafferty K. Am J Clin Nutr 2001 · PMID 11522558 · DOI 10.1093/ajcn/74.3.343Randomised controlled trialindependent cross-checkabstract checked★ key studyIn a controlled test, cola-type acid did not increase calcium in the urine; only caffeine did, and only slightly.
Phosphoric acid produced no excess urinary calcium.
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 soft-drink ingredients make the body lose calcium.
- How was the study done?
Randomised crossover test of different drinks.
- How many people, animals or samples were studied?
Young women who drink soft drinks daily.
- What was actually found?
Phosphoric acid had no effect; caffeine a small one.
- How large was the observed effect?
About 0.25 mmol extra calcium with caffeine.
- What do the results mean in everyday life?
Cola acid does not 'drain' calcium; drinking cola instead of milk may matter more.
- What are the study's limitations?
Short-term test.
- What does it say about Elawady's specific claim?
Contradicts the mechanism of the claim.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Cannot exclude long-term effects.
No study in this group is marked as key.
Studies with mixed or unclear results (2)
-
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.
-
Soda linked to more hip fractures, cola or not
Fung TT et al.. Am J Clin Nutr 2014 · PMID 25099544 · DOI 10.3945/ajcn.114.083352Cohort studyindependent cross-checkabstract checkedIn 73,572 US nurses, each daily soda was linked to 14% more hip fractures; colas were not worse than other sodas.
Soda linked to hip fracture; no difference between colas and non-colas.
Does the study support the specific claim? Partly · 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?
Examine soda and hip fractures.
- How was the study done?
Prospective cohort over up to 30 years.
- How many people, animals or samples were studied?
73,572 women; 1873 fractures.
- What was actually found?
More soda, more fractures; regular and diet alike; cola not special.
- How large was the observed effect?
RR 1.14 per serving/day.
- What do the results mean in everyday life?
Soda may be a marker of risk; phosphoric acid not shown to be the cause.
- What are the study's limitations?
Observational.
- What does it say about Elawady's specific claim?
Weakens the phosphoric-acid explanation.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Cannot prove causation.
No study in this group is marked as key.
Regional context
Germany / EU
No EU regulatory concern about phosphoric acid at authorised levels was reviewed here.
Egypt
No Egypt-specific data.
What applies in my country?
General scientific assessment
Potentially false Probably false as stated: soda is associated with weaker bones in women, but the phosphoric-acid explanation is contradicted by direct evidence.
The following areas of food safety are relevant to this statement:
- Additives and processing
- Controls, imports, recalls, labelling
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
- Sugar-sweetened beverage consumption and bone health: a systematic review and meta-analysis.. Ahn H, Park YK. Nutr J 2021 · PMID 33952276 · DOI 10.1186/s12937-021-00698-1
- Carbonated beverages and urinary calcium excretion.. Heaney RP, Rafferty K. Am J Clin Nutr 2001 · PMID 11522558 · DOI 10.1093/ajcn/74.3.343
- 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
- Soda consumption and risk of hip fractures in postmenopausal women in the Nurses' Health Study.. Fung TT et al.. Am J Clin Nutr 2014 · PMID 25099544 · DOI 10.3945/ajcn.114.083352