Certain supplements caused specific harms: more hip fractures (vitamin A), kidney stones (vitamin C), falls and fractures (high-dose vitamin D), type 2 diabetes (selenium), and no benefit for knee pain (glucosamine).
Original statement
حين أُخضعت المكملات الفموية الأكثر مبيعاً — من الكالسيوم والبيتا كاروتين وفيتامين E، إلى أوميغا-3 والمتعددات والجلوكوزامين والسيلينيوم وفيتامين A — لاختبارات عشوائية مضبوطة بالغفل وبأحجام كبيرة ومتابعة طويلة، لم تَفِ في الغالب بوعودها؛ بل أن بعضها أحدث ضرراً صريحاً: زيادة في الوفيات، وفي سرطان الرئة والبروستاتا، وفي احتشاء عضلة القلب، وفي الرجفان الأذيني، وفي كسور الورك، وفي حصى الكلى. ما يُسوَّق على أنه «وقاية» انقلب في عدة تجارب إلى مصدر للأذى.
not verbatim – paraphrase. Translation by the project; the Arabic wording is authoritative.
Translation
Certain supplements caused specific harms: more hip fractures (vitamin A), kidney stones (vitamin C), falls and fractures (high-dose vitamin D), type 2 diabetes (selenium), and no benefit for knee pain (glucosamine).
Origin
- Source status
- Archive editors
- Attribution
- Archive editors (eltayebat.com); not verified as Elawady's own words
- Origin
- https://eltayebat.com/rule/oral-supplements/
- Attribution uncertainty
- Written by the archive operators; study selection is the archive's, not necessarily Elawady's.
- Claimed mechanism
Dose-specific toxicity.
- Claimed health effect
Fractures, kidney stones, falls, diabetes.
- Population concerned
Various.
- Geographic restriction by Elawady
none found
Scientific assessment
Potentially true – Some evidence points in favour of the statement, but it is not sufficient for a clear judgement.
Certainty of evidence: low – Further research is likely to change the assessment considerably.
1. What was claimed?
Several supplements caused fractures, kidney stones, falls and diabetes.
2. What is demonstrably correct?
Sanders 2010: fracture RR 1.26 (1.00–1.59), falls RR 1.15 with annual 500,000 IU; Bischoff-Ferrari 2016: more falls with 60,000 IU monthly; Stranges 2007: diabetes HR 1.55 (1.03–2.33) with selenium; Feskanich 2002: hip fracture RR 1.48 for highest vitamin A intake (retinol 1.89); GAIT: glucosamine not better than placebo overall.
3. What is wrong or exaggerated?
The summary generalises dose-specific findings (huge boluses, high retinol) to 'supplements' in general. Vitamin A and vitamin C findings are observational. VITAL (daily 2,000 IU vitamin D) found no excess adverse events.
4. What remains unclear?
The vitamin C kidney-stone letter (Thomas 2013) has no abstract in PubMed and could not be checked here.
5. Which studies support it?
A-SUP-14, A-SUP-15, A-SUP-16, A-SUP-20, A-SUP-21, A-SUP-13.
6. Which studies contradict it?
A-SUP-22 (VITAL: no excess hypercalcaemia or adverse events); Endocrine Society 2024 (I-SUP-05) prefers daily over intermittent high doses.
7. What applies to Germany and Europe?
Applies equally.
8. What is known about Egypt?
Applies equally.
9. What practical conclusion is appropriate?
Avoid very high or intermittent mega-doses and high-dose retinol; moderate daily doses for a clear indication are a different matter.
Assessment details
- Rationale for certainty of evidence
Evidence is mixed in quality: annual 500,000 IU vitamin D increased falls and fractures in an RCT; monthly 60,000 IU increased falls versus 24,000 IU in a small RCT; selenium increased diabetes as a secondary outcome of one RCT; vitamin A/hip fracture and vitamin C/kidney stones come from observational data; GAIT found no overall benefit of glucosamine. USPSTF 2022 called the evidence for these harms 'limited'.
- Source quality
Correct citations; harms are regimen- and dose-specific.
- Regional transferability
High.
- Individual exceptions
Daily moderate-dose vitamin D in deficient people is a different situation from large intermittent boluses.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 26 October 2026 provisional
Scientific evidence in detail
True only under certain conditions – The claim holds only for certain doses, groups of people, preparations or circumstances.
Research question: Do specific supplement regimens cause specific harms (vitamin A - hip fracture; vitamin C - kidney stones; high-dose vitamin D - falls/fractures; selenium - type 2 diabetes) and does glucosamine fail to relieve knee pain?
Research question in detail (PICO)
- Population
- Various adult populations
- Intervention or exposure
- High-dose vitamin A, vitamin C, bolus vitamin D, selenium; glucosamine
- Comparison
- Placebo / low intake
- Geographic scope
- universal biology
- Outcomes
- Hip fracture
- Kidney stones
- Falls/fractures
- Type 2 diabetes
- Knee pain
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
Yearly vitamin D mega-dose
Sanders KM et al.. JAMA 2010 · PMID 20460620 · DOI 10.1001/jama.2010.594 Randomised controlled trialabstract checkedAnnual 500,000 IU vitamin D increased falls and fractures.
- Actual result
- Falls RR 1.15 (1.02-1.30); fractures RR 1.26 (1.00-1.59).
- Methodological quality
- high (RCT)
- Relevance
- direct
- Limitations
- One regimen.
Selenium for preventing cancer: Cochrane review
Vinceti M et al.. Cochrane Database Syst Rev 2018 · PMID 29376219 · DOI 10.1002/14651858.CD005195.pub4 Meta-analysisabstract checkednewly addedCochrane: selenium did not prevent cancer; RCTs showed slightly more type 2 diabetes.
- Actual result
- Cancer RR 1.01 (0.93-1.10); diabetes increase not quantified in abstract.
- Methodological quality
- high (Cochrane)
- Relevance
- direct
Glucosamine for knee and hip arthritis
Runhaar J et al.. Ann Rheum Dis 2017 · PMID 28754801 · DOI 10.1136/annrheumdis-2017-211149 Meta-analysisabstract checkednewly addedIPD meta-analysis: glucosamine no better than placebo.
- Actual result
- No benefit at 3 or 24 months.
- Methodological quality
- high
- Relevance
- direct
- Limitations
- Data from 6 of 21 trials.
What speaks against the claim?
VITAL: vitamin D for prevention
Manson JE et al.. N Engl J Med 2019 · PMID 30415629 · DOI 10.1056/NEJMoa1809944 Randomised controlled trialabstract checkedVITAL: daily 2,000 IU vitamin D had no excess adverse events.
- Actual result
- No excess hypercalcaemia.
- Methodological quality
- high (RCT)
- Relevance
- direct
Large intermittent doses of vitamin D and falls
Myung SK et al.. Osteoporos Int 2023 · PMID 37120684 · DOI 10.1007/s00198-023-06761-3 Meta-analysisabstract checkednewly addedMeta-analysis of bolus vitamin D: no significant increase in falls or fractures overall.
- Actual result
- Falls RR 1.03 (0.98-1.09); fractures 0.99 (0.87-1.14).
- Methodological quality
- moderate
- Relevance
- direct
- Limitations
- P value inconsistent with CI.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
Harms are regimen-specific: bolus vitamin D (one RCT), selenium-diabetes (RCTs), vitamin C stones in men (cohorts), vitamin A hip fracture (cohort); glucosamine lacks benefit.
Why some studies weigh more
RCT findings weigh more than cohort associations; pooled bolus-dose data temper the vitamin D harm.
Is a causal relationship established? Possible, not established Probable for selenium-diabetes and bolus vitamin D-falls in specific trials; not established for vitamin A and vitamin C.
Remaining uncertainty
Size of risks; doses.
Justified conclusion
Partly true for specific high-dose regimens; 'caused' is too strong for observational findings.
Why do studies seem to disagree?
Sanders (single annual bolus) vs VITAL (daily moderate dose): different regimens. Vitamin C stones in men but not women: sex-specific or chance.
Does this depend on the country?
- General biological effects
- Same human physiology everywhere.
- Eating habits
- Supplement use patterns differ by country; not region-specific for this question.
- Origin of the food
- Not relevant.
- Contaminants
- Product quality and contamination vary by market (not assessed here).
- National production conditions
- Not relevant.
- Legal rules
- Supplements are regulated as foods in the EU; Egyptian rules not verified.
- Actual monitoring data
- No monitoring data reviewed.
A regional difference that changes the conclusion is not supported by robust data.
Statistical re-check
- Consistency of P with CI – Reported P=0.051 vs recomputed P about 0.13 from 0.99-1.15: misreporting. recalculated
- Absolute excess – 4.2 extra T2D cases per 1,000 person-years; NNH about 238 per year. recalculated
- P from CI – P about 0.04 for HR 1.19 (1.01-1.40). recalculated
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- Specific harms of high-dose regimens
- Starting level
- low (observational studies)
- Reasons for downgrading
- inconsistency across agents
- imprecision
- 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.
Clinical guidelines and official statements checked
- Endocrine Society: Vitamin D for the Prevention of Disease (I-SUP-05) (2024) · Original publication
Suggests empiric vitamin D for ages 1-18 (rickets prevention), adults >75, pregnancy and high-risk prediabetes; daily rather than intermittent high doses in people >50; against empiric supplementation above the DRI in healthy adults <75 (abstract re-read 2026-10-26; two errata recorded).
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 | TITLE:selenium AND TITLE:"preventing cancer" AND JOURNAL:"Cochrane Database Syst Rev" | supporting evidence | 3 | |
| Europe PMC | 26 October 2026 | TITLE:"vitamin D" AND (TITLE:falls OR TITLE:fractures) AND (TITLE:bolus OR TITLE:"high dose" OR TITLE:"intermittent" OR TITLE:"dosing") AND (PUB_TYPE:"Meta-Analysis") | both directions | 1 | |
| Europe PMC | 26 October 2026 | (TITLE:"vitamin C" OR TITLE:ascorbic) AND TITLE:"kidney stone*" | both directions | 7 | |
| Europe PMC | 26 October 2026 | EXT_ID:23381591 AND SRC:MED | both directions | 1 | |
| Europe PMC | 26 October 2026 | "vitamin C" AND "kidney stones" AND (TITLE:supplemental OR TITLE:intake) AND (TITLE:incident OR TITLE:risk) | both directions | 18 | |
| Europe PMC | 26 October 2026 | TITLE:glucosamine AND TITLE:knee AND (PUB_TYPE:"Meta-Analysis") AND PUB_YEAR:[2015 TO 2026] | both directions | 9 |
How deeply was this checked?
13 linked studies: 0 checked in full text (0 of them with a structured risk-of-bias assessment), 13 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: Potentially true (low)
- 26 October 2026 · Phase 4 (systematic evidence review) · Re-examined with extended evidence; verdict unchanged: Potentially true (low)
New sources support individual parts but remain regimen-specific and partly observational; verdict kept.
New sources: I-SUP-115 I-SUP-116 I-SUP-117 I-SUP-118
In plain language
Some trials found harm from very large doses: a single huge yearly dose of vitamin D increased falls and fractures in older women, and selenium pills may have raised diabetes. Other links, such as vitamin A with hip fractures, come from observational studies. These results warn against mega-doses, not against every vitamin pill.
Studies on this claim
Studies supporting the claim (8)
-
Yearly vitamin D mega-dose
Sanders KM et al.. JAMA 2010 · PMID 20460620 · DOI 10.1001/jama.2010.594Randomised controlled trialcited by the Tayebat archiveabstract checkedMore falls and fractures with 500,000 IU once a year.
Does the study support the specific claim? Yes · 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?
Falls prevention.
- How was the study done?
RCT.
- How many people, animals or samples were studied?
2,256 women.
- What was actually found?
More falls and fractures.
- How large was the observed effect?
RR 1.15; 1.26.
- What do the results mean in everyday life?
Avoid mega-doses.
- What are the study's limitations?
Regimen-specific.
- What does it say about Elawady's specific claim?
Supports for this regimen.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Daily doses.
-
High monthly vitamin D and falls
Bischoff-Ferrari HA et al.. JAMA Intern Med 2016 · PMID 26747333 · DOI 10.1001/jamainternmed.2015.7148Randomised controlled trialcited by the Tayebat archiveabstract checkedMore people fell with the higher monthly doses.
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?
Function and falls.
- How was the study done?
RCT.
- How many people, animals or samples were studied?
200.
- What was actually found?
More falls.
- How large was the observed effect?
67% vs 48%.
- What do the results mean in everyday life?
Avoid high boluses.
- What are the study's limitations?
Small.
- What does it say about Elawady's specific claim?
Partly supports.
- Do the results apply to Germany and Europe?
Swiss.
- What can explicitly not be concluded from this study?
Daily doses.
-
Selenium and diabetes
Stranges S et al.. Ann Intern Med 2007 · PMID 17620655 · DOI 10.7326/0003-4819-147-4-200708210-00175Randomised controlled trialcited by the Tayebat archiveabstract checkedSelenium pills were linked to more new diabetes (HR 1.55).
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?
Diabetes with selenium.
- How was the study done?
RCT secondary analysis.
- How many people, animals or samples were studied?
1,202.
- What was actually found?
More diabetes.
- How large was the observed effect?
HR 1.55.
- What do the results mean in everyday life?
Avoid selenium pills.
- What are the study's limitations?
Secondary outcome.
- What does it say about Elawady's specific claim?
Partly supports.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Firm harm.
-
Vitamin A and hip fractures
Feskanich D et al.. JAMA 2002 · PMID 11754708 · DOI 10.1001/jama.287.1.47Cohort studycited by the Tayebat archiveabstract checkedWomen with the highest retinol intake had about 1.9 times the risk of hip fracture.
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?
Retinol and fractures.
- How was the study done?
Cohort.
- How many people, animals or samples were studied?
72,337.
- What was actually found?
More fractures with high retinol.
- How large was the observed effect?
RR 1.89.
- What do the results mean in everyday life?
Avoid high retinol.
- What are the study's limitations?
Observational.
- What does it say about Elawady's specific claim?
Partly supports.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Causation.
-
Glucosamine for knee pain (GAIT)
Clegg DO et al.. N Engl J Med 2006 · PMID 16495392 · DOI 10.1056/NEJMoa052771Randomised controlled trialcited by the Tayebat archiveabstract checkedNot better than placebo overall.
Does the study support the specific claim? Yes · 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?
Knee OA pain.
- How was the study done?
RCT.
- How many people, animals or samples were studied?
1,583.
- What was actually found?
No overall benefit.
- How large was the observed effect?
+3.9 points n.s.
- What do the results mean in everyday life?
Little benefit.
- What are the study's limitations?
Subgroup.
- What does it say about Elawady's specific claim?
Supports.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Harm.
-
Vitamin C pills and kidney stones
Ferraro PM et al.. Am J Kidney Dis 2016 · PMID 26463139 · DOI 10.1053/j.ajkd.2015.09.005Cohort studyindependent cross-checkabstract checkedMen taking 1,000 mg or more of vitamin C a day had about 19% more kidney stones; no link was seen in women.
High-dose supplemental vitamin C associated with kidney stones in men (HR 1.19 at >=1000 mg/d).
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?
To link vitamin C intake to kidney stones.
- How was the study done?
Three large cohort studies.
- How many people, animals or samples were studied?
About 197,000 adults.
- What was actually found?
Higher stone risk with high-dose vitamin C in men only.
- How large was the observed effect?
HR 1.19 (1.01-1.40).
- What do the results mean in everyday life?
Avoid high-dose vitamin C if prone to stones.
- What are the study's limitations?
Observational; questionnaires.
- What does it say about Elawady's specific claim?
Supports part of C-SUP-07.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Cannot prove that vitamin C causes stones.
-
Selenium for preventing cancer: Cochrane review
Vinceti M et al.. Cochrane Database Syst Rev 2018 · PMID 29376219 · DOI 10.1002/14651858.CD005195.pub4Meta-analysisindependent cross-checkabstract checkedSelenium pills did not prevent cancer, and trials hinted at more type 2 diabetes.
RCTs showed a slightly increased risk of type 2 diabetes with selenium.
Does the study support the specific claim? Yes · 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?
To test selenium for cancer prevention.
- How was the study done?
Cochrane review of trials and cohorts.
- How many people, animals or samples were studied?
10 trials (27,232 people); 70 cohorts.
- What was actually found?
No cancer prevention; possible more diabetes and high-grade prostate cancer in some.
- How large was the observed effect?
Cancer RR 1.01 (0.93-1.10).
- What do the results mean in everyday life?
Selenium pills are not useful for cancer prevention.
- What are the study's limitations?
Diabetes risk not quantified here.
- What does it say about Elawady's specific claim?
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Not about selenium-deficient regions.
-
Glucosamine for knee and hip arthritis
Runhaar J et al.. Ann Rheum Dis 2017 · PMID 28754801 · DOI 10.1136/annrheumdis-2017-211149Meta-analysisindependent cross-checkabstract checkedUsing raw data from five independent trials, glucosamine was no better than a dummy pill for pain or function.
Glucosamine not better than placebo for knee/hip OA pain or function.
Does the study support the specific claim? Yes · 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?
To test glucosamine in osteoarthritis subgroups.
- How was the study done?
Individual patient data meta-analysis.
- How many people, animals or samples were studied?
1,625 patients in placebo trials.
- What was actually found?
No benefit overall or in any subgroup.
- How large was the observed effect?
Not given.
- What do the results mean in everyday life?
Glucosamine is unlikely to help arthritis pain.
- What are the study's limitations?
Not all trials shared data.
- What does it say about Elawady's specific claim?
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Cannot rule out effects of specific products.
No study in this group is marked as key.
Studies contradicting or limiting the claim (2)
-
VITAL: vitamin D for prevention
Manson JE et al.. N Engl J Med 2019 · PMID 30415629 · DOI 10.1056/NEJMoa1809944Randomised controlled trialcited by the Tayebat archiveabstract checkedNo prevention of cancer or heart disease; no safety problems.
Does the study support the specific claim? Yes · 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?
Prevention.
- How was the study done?
RCT.
- How many people, animals or samples were studied?
25,871.
- What was actually found?
Null.
- How large was the observed effect?
HR 0.96/0.97.
- What do the results mean in everyday life?
No need in replete adults.
- What are the study's limitations?
Replete population.
- What does it say about Elawady's specific claim?
Supports C-SUP-01.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Effect in deficiency.
-
Endocrine Society 2024 vitamin D guideline
Demay MB et al.. J Clin Endocrinol Metab 2024 · PMID 38828931 · DOI 10.1210/clinem/dgae290Guideline / position statementindependent cross-checkabstract checkedSuggests vitamin D for children, pregnancy, people ≥75 and high-risk prediabetes.
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?
Vitamin D for prevention.
- How was the study done?
Guideline.
- What was actually found?
Group-specific suggestions.
- What do the results mean in everyday life?
Some groups benefit.
- What are the study's limitations?
Conditional.
- What does it say about Elawady's specific claim?
Contradicts blanket ban.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Doses.
No study in this group is marked as key.
Studies with mixed or unclear results (3)
-
Vitamin C pills and kidney stones
Thomas LD et al.. JAMA Intern Med 2013 · PMID 23381591 · DOI 10.1001/jamainternmed.2013.2296Cohort studycited by the Tayebat archiveabstract checkedNot read (no abstract).
Does the study support the specific claim? Unclear · 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?
Kidney stones and vitamin C.
- How was the study done?
Cohort letter.
- How many people, animals or samples were studied?
Not read.
- What was actually found?
Not read.
- How large was the observed effect?
Not read.
- What are the study's limitations?
No abstract.
- What does it say about Elawady's specific claim?
Cannot judge.
- What can explicitly not be concluded from this study?
Anything specific.
-
HOPE-2: B vitamins in vascular disease
Lonn E et al.. N Engl J Med 2006 · PMID 16531613 · DOI 10.1056/NEJMoa060900Randomised controlled trialcited by the Tayebat archiveabstract checkedNo reduction in major CV events; fewer strokes.
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?
CV prevention.
- How was the study done?
RCT.
- How many people, animals or samples were studied?
5,522.
- What was actually found?
Null primary.
- How large was the observed effect?
RR 0.95.
- What do the results mean in everyday life?
Not for CV prevention.
- What does it say about Elawady's specific claim?
Mixed.
- Do the results apply to Germany and Europe?
Applicable.
-
Large intermittent doses of vitamin D and falls
Myung SK et al.. Osteoporos Int 2023 · PMID 37120684 · DOI 10.1007/s00198-023-06761-3Meta-analysisindependent cross-checkabstract checkedLarge doses given monthly or yearly did not prevent falls or fractures and might slightly increase falls.
High-dose bolus vitamin D: no benefit, borderline increase in falls, no increase in fractures.
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?
To check high-dose bolus vitamin D for falls and fractures.
- How was the study done?
Meta-analysis of 15 trials.
- How many people, animals or samples were studied?
15 trials.
- What was actually found?
No benefit; possible slight increase in falls.
- How large was the observed effect?
Falls RR 1.03 (0.98-1.09).
- What do the results mean in everyday life?
Avoid huge occasional doses unless prescribed.
- What are the study's limitations?
P value and CI inconsistent.
- What does it say about Elawady's specific claim?
Partly supports C-SUP-07 (falls), not fractures.
- Do the results apply to Germany and Europe?
Applicable.
- What can explicitly not be concluded from this study?
Not about daily moderate doses.
No study in this group is marked as key.
Regional context
Germany / EU
Applies equally.
Egypt
Applies equally.
What applies in my country?
General scientific assessment
Potentially true Possibly true for specific high-dose regimens; not a general verdict on supplements.
This statement concerns biological or medical relationships. The scientific assessment above applies regardless of the country; country-specific food data do not change it.
References
- Annual high-dose oral vitamin D and falls and fractures in older women: a randomized controlled trial.. Sanders KM et al.. JAMA 2010 · PMID 20460620 · DOI 10.1001/jama.2010.594
- Monthly High-Dose Vitamin D Treatment for the Prevention of Functional Decline: A Randomized Clinical Trial.. Bischoff-Ferrari HA et al.. JAMA Intern Med 2016 · PMID 26747333 · DOI 10.1001/jamainternmed.2015.7148
- Effects of long-term selenium supplementation on the incidence of type 2 diabetes: a randomized trial.. Stranges S et al.. Ann Intern Med 2007 · PMID 17620655 · DOI 10.7326/0003-4819-147-4-200708210-00175
- Vitamin A intake and hip fractures among postmenopausal women.. Feskanich D et al.. JAMA 2002 · PMID 11754708 · DOI 10.1001/jama.287.1.47
- Glucosamine, chondroitin sulfate, and the two in combination for painful knee osteoarthritis.. Clegg DO et al.. N Engl J Med 2006 · PMID 16495392 · DOI 10.1056/NEJMoa052771
- Total, Dietary, and Supplemental Vitamin C Intake and Risk of Incident Kidney Stones.. Ferraro PM et al.. Am J Kidney Dis 2016 · PMID 26463139 · DOI 10.1053/j.ajkd.2015.09.005
- Selenium for preventing cancer.. Vinceti M et al.. Cochrane Database Syst Rev 2018 · PMID 29376219 · DOI 10.1002/14651858.CD005195.pub4
- Subgroup analyses of the effectiveness of oral glucosamine for knee and hip osteoarthritis: a systematic review and individual patient data meta-analysis from the OA trial bank.. Runhaar J et al.. Ann Rheum Dis 2017 · PMID 28754801 · DOI 10.1136/annrheumdis-2017-211149
- Vitamin D Supplements and Prevention of Cancer and Cardiovascular Disease.. Manson JE et al.. N Engl J Med 2019 · PMID 30415629 · DOI 10.1056/NEJMoa1809944
- Vitamin D for the Prevention of Disease: An Endocrine Society Clinical Practice Guideline.. Demay MB et al.. J Clin Endocrinol Metab 2024 · PMID 38828931 · DOI 10.1210/clinem/dgae290
- Ascorbic acid supplements and kidney stone incidence among men: a prospective study.. Thomas LD et al.. JAMA Intern Med 2013 · PMID 23381591 · DOI 10.1001/jamainternmed.2013.2296
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