Long-term registry data link removal of tonsils, appendix, gallbladder, uterus, ovaries and spleen to higher rates of respiratory disease, autoimmunity, cardiovascular events, gastrointestinal cancers and dementia; each organ does work the body never fully replaces.
Original statement
الأدلة طويلة الأمد ترصد ارتفاعاً معتبراً في أمراض الجهاز التنفسي والمناعة الذاتية والقلب والشرايين والسرطانات الهضمية والخرف بعد هذه الجراحات
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
Long-term registry data link removal of tonsils, appendix, gallbladder, uterus, ovaries and spleen to higher rates of respiratory disease, autoimmunity, cardiovascular events, gastrointestinal cancers and dementia; each organ does work the body never fully replaces.
Origin
- Source status
- Archive editors
- Attribution
- Archive editors (eltayebat.com); not necessarily Elawady's own words
- Origin
- https://eltayebat.com/rule/unnecessary-organ-removal/
- Attribution uncertainty
- Editorial summary/narrative and study selection written by the archive operators; the archive states that the cited research documents harm independently of Dr. Diaa's words.
- Claimed mechanism
Loss of immune, metabolic, hormonal function.
- Claimed health effect
Multiple chronic diseases.
- Population concerned
Patients after organ removal
- Geographic restriction by Elawady
not applicable
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?
Broad long-term harms after organ removal.
2. What is demonstrably correct?
Associations reported for tonsils/adenoids (A-ORG-01, A-ORG-02), gallbladder (A-ORG-06, A-ORG-09), ovaries (A-ORG-13, A-ORG-14, A-ORG-15, I-ORG-10), uterus in younger women (A-ORG-10, A-ORG-11), spleen (A-ORG-16, A-ORG-18).
3. What is wrong or exaggerated?
Several archive-cited studies limit the claim: no excess GI cancer after appendectomy (A-ORG-05), no increased mortality after hysterectomy (A-ORG-12), part of splenectomy CV risk explained by underlying disease (A-ORG-17); appendectomy was linked to lower UC risk (A-ORG-04). Causality is rarely established.
4. What remains unclear?
Causal size of each association.
5. Which studies support it?
A-ORG-01, A-ORG-02, A-ORG-06, A-ORG-10, A-ORG-11, A-ORG-13, A-ORG-14, A-ORG-15, A-ORG-16.
6. Which studies contradict it?
A-ORG-04, A-ORG-05, A-ORG-12, A-ORG-17.
7. What applies to Germany and Europe?
Most cited cohorts are Scandinavian (Denmark, Sweden) and directly European; RCTs from the UK and Finland are directly transferable. Guidelines in Europe also emphasize defined indications (not verified here in detail).
8. What is known about Egypt?
No Egypt-specific data on rates or outcomes of tonsillectomy, cholecystectomy, hysterectomy, splenectomy or thyroid surgery were identified in this review.
9. What practical conclusion is appropriate?
Long-term risks are a legitimate part of informed consent for elective/borderline operations; they do not argue against indicated surgery.
Assessment details
- Rationale for certainty of evidence
Many associations are reported, but nearly all are observational with confounding by indication; several archive-cited studies show null or limiting results.
- Source quality
Archive summary; the narrative's balanced conclusion ('when an operation is genuinely indicated, do it without hesitation') is consistent with the evidence.
- Regional transferability
Mostly Scandinavian data.
- Individual exceptions
Risks depend strongly on organ, age at surgery and indication.
- 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: Do long-term registry data show that removal of tonsils, appendix, gallbladder, uterus, ovaries and spleen causes higher rates of respiratory, autoimmune, cardiovascular, gastrointestinal-cancer and dementia outcomes, because each organ's work is never fully replaced?
Research question in detail (PECO)
- Population
- People after removal of these organs
- Intervention or exposure
- Organ removal
- Comparison
- People without removal (ideally with the same indication)
- Geographic scope
- universal biology
- Outcomes
- Respiratory disease
- Autoimmunity
- CVD
- GI cancers
- Dementia
- Infection
Study results as reported by the authors. Our assessment follows below.
What speaks for the claim?
Infections after spleen removal in Denmark
Thomsen RW et al.. Ann Intern Med 2009 · PMID 19841456 · DOI 10.7326/0003-4819-151-8-200910200-00008 Cohort studyabstract checkednewly addedSplenectomy: lasting infection risk (well established).
- Actual result
- HR 2.5 after 1 year vs population.
- Methodological quality
- high
- Relevance
- direct
Removing ovaries at hysterectomy and long-term survival
Cusimano MC et al.. BMJ 2021 · PMID 34880044 · DOI 10.1136/bmj-2021-067528 Cohort studyfull text checkednewly addedPremenopausal BSO: higher long-term mortality.
- Actual result
- HR 1.31 (<45).
- Methodological quality
- high
- Relevance
- direct
- Limitations
- Only before 50.
What speaks against the claim?
Tonsil removal and bowel inflammation: the family test
Bager P et al.. Epidemiology 2019 · PMID 30461527 · DOI 10.1097/EDE.0000000000000946 Cohort studyabstract checkednewly addedFamily study: tonsillectomy-IBD association also present in relatives, indicating confounding.
- Actual result
- Crohn RR 1.22 for relatives.
- Methodological quality
- high
- Relevance
- indirect
- Limitations
- IBD only.
Do tonsil and adenoid operations change later infections in children?
Kim JY et al.. Laryngoscope 2021 · PMID 33720418 · DOI 10.1002/lary.29506 Cohort studyabstract checkednewly addedMatched cohort: no increase in airway infections after adenotonsillectomy.
- Actual result
- Equivalence over 9 years.
- Methodological quality
- moderate
- Relevance
- direct
- Limitations
- Children.
Genetic test of gallbladder removal and bowel cancer
Chen L et al.. Chin Med J (Engl) 2023 · PMID 37027252 · DOI 10.1097/CM9.0000000000002612 Otherabstract checkednewly addedMR: no causal effect of cholecystectomy on CRC.
- Actual result
- OR 1.54 (0.61-3.92).
- Methodological quality
- moderate
- Relevance
- indirect
- Limitations
- Weak instruments.
What does the overall evidence say?
Editorial assessment based on the studies above – not itself a study result.
Which position is better supported?
Some long-term consequences are well established (infection after splenectomy) or probable (mortality/CVD after premenopausal oophorectomy); many other registry associations (tonsils, appendix, gallbladder) are small and partly explained by confounding.
Why some studies weigh more
Each organ judged separately (see C-ORG-03 to -13); designs controlling for indication or family weigh most.
Is a causal relationship established? Possible, not established Varies by organ: established for spleen; probable for ovaries; not established for tonsils, appendix, gallbladder.
Remaining uncertainty
Causal share for most associations.
Justified conclusion
Partly correct; the general statement overgeneralises from a few strong findings.
Why do studies seem to disagree?
The bundle mixes established effects (spleen), probable effects (ovaries) and confounded associations (tonsils, gallbladder); disagreement among studies reflects comparator choice (population vs indication-matched vs family).
Does this depend on the country?
- General biological effects
- Universal.
- Eating habits
- Not relevant to this claim.
- Origin of the food
- Not applicable.
- Contaminants
- Not applicable.
- National production conditions
- Not applicable.
- Legal rules
- Not applicable.
- Actual monitoring data
- No Egypt-specific monitoring data identified.
A regional difference that changes the conclusion is not supported by robust data.
Statistical re-check
- Absolute excess – About 1 extra autoimmune case per 4700 person-years recalculated
Certainty of the overall evidence (GRADE, simplified)
- Main outcome
- Long-term harms caused by organ removal (bundle)
- Starting level
- low (observational studies)
- Reasons for downgrading
- inconsistency
- risk of bias
- 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
- Spleen Australia: Guidelines for the prevention of sepsis in patients with asplenia and hyposplenism in Australia and New Zealand (2017) · Original publication
Asplenia/hyposplenism carries increased risk of fulminant sepsis with high mortality; recommends vaccination protocols and antimicrobial prophylaxis (abstract; I-ORG-116). - ACOG: Committee Opinion No. 774: Opportunistic Salpingectomy as a Strategy for Epithelial Ovarian Cancer Prevention (reaffirmed 2024) (2019) · Original publication
BSO causing surgical menopause reduces ovarian cancer risk but may increase the risk of cardiovascular disease, other cancers, osteoporosis, cognitive impairment and all-cause mortality; counselling should include oophorectomy (I-ORG-142).
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 | (organ removal OR appendectomy OR tonsillectomy OR cholecystectomy OR splenectomy OR hysterectomy) AND long-term[ti] AND (sibling[tiab] OR confounding[tiab]) AND cohort[tiab] | contradicting evidence | 9 | |
| Europe PMC | 26 October 2026 | (TITLE:tonsillectomy OR TITLE:adenoidectomy OR TITLE:adenotonsillectomy) AND (TITLE:"long-term" OR TITLE:"later life" OR TITLE:risk) AND (TITLE:respiratory OR TITLE:asthma OR TITLE:allergic OR TITLE:infections OR TITLE:infectious) AND (cohort OR registry OR "population-based") | both directions | 15 | |
| Europe PMC | 26 October 2026 | (TITLE:tonsillectomy OR TITLE:adenotonsillectomy) AND (TITLE:autoimmune OR TITLE:"multiple sclerosis" OR TITLE:"inflammatory bowel" OR TITLE:"Crohn") AND (TITLE:"meta-analysis" OR cohort OR "population-based") | both directions | 13 | |
| Europe PMC | 26 October 2026 | (TITLE:oophorectomy OR TITLE:"ovarian conservation" OR TITLE:"salpingo-oophorectomy" OR TITLE:"ovarian tissue") AND (TITLE:mortality OR TITLE:death) AND (hysterectomy) AND (cohort OR "population-based" OR "meta-analysis") | both directions | 17 | |
| Europe PMC | 26 October 2026 | (TITLE:splenectomy OR TITLE:splenectomised OR TITLE:splenectomized OR TITLE:asplenia) AND (TITLE:infection OR TITLE:sepsis OR TITLE:"venous thromboembolism" OR TITLE:thrombosis) AND (cohort OR "population-based") | both directions | 70 | |
| PubMed | 26 October 2026 | Thomsen RW[au] AND splenectomy | supporting evidence | 3 | |
| Europe PMC | 26 October 2026 | (TITLE:cholecystectomy) AND (TITLE:"colorectal cancer" OR TITLE:"colon cancer" OR TITLE:"small bowel" OR TITLE:"small intestine" OR TITLE:"intestinal cancer" OR TITLE:"digestive cancer" OR TITLE:"gastrointestinal cancer") AND (TITLE:"meta-analysis" OR cohort OR "population-based" OR "Mendelian") | both directions | 43 |
Open questions
Family- or indication-controlled designs for all organs.
How deeply was this checked?
22 linked studies: 3 checked in full text (1 of them with a structured risk-of-bias assessment), 19 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)
Unchanged (“Potentially true”, low).
New sources: I-ORG-115 I-ORG-123 I-ORG-122 I-ORG-124 I-ORG-131 I-ORG-134
In plain language
The archive says that removing organs such as tonsils, gallbladder, uterus, ovaries or spleen is linked to many later diseases. Some links are real and fairly consistent, especially removing ovaries early and spleen-related infections. Others are uncertain because the people who need these operations may already be at higher risk. Some studies cited by the archive found no harm. The archive itself concludes that operations that are really needed should be done.
Studies on this claim
Studies supporting the claim (11)
-
Danish children: tonsil/adenoid removal and later illness
Byars SG et al.. JAMA Otolaryngol Head Neck Surg 2018 · PMID 29879264 · DOI 10.1001/jamaoto.2018.0614Cohort studycited by the Tayebat archiveabstract checked★ key studyChildren who had the operations had more respiratory illnesses later (2-3 times for upper airway disease), but the study cannot prove the operation caused it.
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?
Long-term risk
- How was the study done?
Register cohort
- How many people, animals or samples were studied?
1.19 million
- What was actually found?
Associations with later respiratory/infectious/allergic disease
- How large was the observed effect?
RR 1.99-2.72; infections +2.14% absolute
- What do the results mean in everyday life?
A reason to avoid unnecessary operations
- What are the study's limitations?
Confounding
- What does it say about Elawady's specific claim?
Supports a cautious approach, not a ban
- Do the results apply to Germany and Europe?
Directly European
- What can explicitly not be concluded from this study?
That surgery causes the diseases
-
Sweden: autoimmune diseases after tonsil removal
Ji J et al.. J Autoimmun 2016 · PMID 27344241 · DOI 10.1016/j.jaut.2016.06.007Cohort studycited by the Tayebat archiveabstract checked★ key studyPeople who had tonsils removed were diagnosed with autoimmune diseases 34% more often than the general population.
Does the study support the specific claim? Partly · 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?
Autoimmunity
- How was the study done?
Cohort vs population
- How many people, animals or samples were studied?
179,875
- What was actually found?
Higher incidence
- How large was the observed effect?
SIR 1.34
- What do the results mean in everyday life?
Possible link; cause unclear
- What are the study's limitations?
No matched controls
- What does it say about Elawady's specific claim?
Association only
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
Causation
-
Gallbladder removal and bowel cancer
Lagergren J et al.. Gastroenterology 2001 · PMID 11522737 · DOI 10.1053/gast.2001.27083Cohort studycited by the Tayebat archiveabstract checked★ key studyAfter gallbladder removal, rare small-bowel cancers were about 1.8 times as frequent and right-sided colon cancer 1.16 times as frequent as in the population.
Does the study support the specific claim? Partly · 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?
Cancer risk
- How was the study done?
Register
- How many people, animals or samples were studied?
278,460
- What was actually found?
Higher proximal bowel cancer
- How large was the observed effect?
SIR 1.77/1.16
- What do the results mean in everyday life?
Small extra risk of rare cancers
- What are the study's limitations?
No confounder control
- What does it say about Elawady's specific claim?
Partly supports
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
Causation; absolute size
-
Hysterectomy and heart disease in Sweden
Ingelsson E et al.. Eur Heart J 2011 · PMID 21186237 · DOI 10.1093/eurheartj/ehq477Cohort studycited by the Tayebat archiveabstract checkedWomen operated before 50 had about 18% more cardiovascular disease later.
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?
CVD
- How was the study done?
Register
- How many people, animals or samples were studied?
824,484
- What was actually found?
Higher CVD <50
- How large was the observed effect?
HR 1.18
- What do the results mean in everyday life?
Possible long-term cost
- What are the study's limitations?
Confounding
- What does it say about Elawady's specific claim?
Supports association
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
Causation
-
Hysterectomy with ovaries kept
Laughlin-Tommaso SK et al.. Menopause 2018 · PMID 29286988 · DOI 10.1097/GME.0000000000001043Cohort studycited by the Tayebat archiveabstract checkedLater heart and metabolic problems were modestly more frequent, especially after surgery at age 35 or younger.
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?
CV risk
- How was the study done?
Cohort
- How many people, animals or samples were studied?
4188
- What was actually found?
Modest increase
- How large was the observed effect?
CAD HR 1.33
- What do the results mean in everyday life?
Consider alternatives when possible
- What are the study's limitations?
Observational
- What does it say about Elawady's specific claim?
Supports association
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Causation
-
Nurses' Health Study: removing both ovaries at hysterectomy
Parker WH et al.. Obstet Gynecol 2013 · PMID 23635669 · DOI 10.1097/AOG.0b013e3182864350Cohort studycited by the Tayebat archivefull text checked★ key studyRemoving the ovaries was linked to somewhat higher death rates (16.8% vs 13.3% over 28 years), mainly in women under 50 who never took estrogen.
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?
Mortality
- How was the study done?
Prospective cohort
- How many people, animals or samples were studied?
30,117
- What was actually found?
Higher mortality, especially <50 without estrogen
- How large was the observed effect?
HR 1.13; NNH 8 in subgroup
- What do the results mean in everyday life?
Keeping healthy ovaries may be better for many women
- What are the study's limitations?
Observational
- What does it say about Elawady's specific claim?
Supports direction; NNH misused
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Causation; women with BRCA etc.
-
Ovary removal before menopause and dementia
Rocca WA et al.. Neurology 2007 · PMID 17761551 · DOI 10.1212/01.wnl.0000276984.19542.e6Cohort studycited by the Tayebat archiveabstract checked★ key studyWomen who had ovaries removed before menopause had 46% higher risk of cognitive impairment or dementia later.
Does the study support the specific claim? Yes · 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?
Dementia
- How was the study done?
Cohort
- How many people, animals or samples were studied?
2961
- What was actually found?
Higher risk
- How large was the observed effect?
HR 1.46
- What do the results mean in everyday life?
Possible brain cost of early ovary removal
- What are the study's limitations?
Observational
- What does it say about Elawady's specific claim?
Supports association
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Causation
-
Ovary removal and chronic diseases
Rocca WA et al.. Mayo Clin Proc 2016 · PMID 27693001 · DOI 10.1016/j.mayocp.2016.08.002Cohort studycited by the Tayebat archiveabstract checkedWomen who had both ovaries removed before 46 accumulated chronic diseases faster.
Does the study support the specific claim? Yes · 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?
Multimorbidity
- How was the study done?
Cohort
- How many people, animals or samples were studied?
n/a
- What was actually found?
Faster accumulation
- How large was the observed effect?
HR 1.22
- What do the results mean in everyday life?
Possible broad health cost
- What are the study's limitations?
Baseline differences
- 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?
Causation
-
Long-term risks after spleen removal in US veterans
Kristinsson SY et al.. Haematologica 2014 · PMID 24056815 · DOI 10.3324/haematol.2013.092460Cohort studycited by the Tayebat archiveabstract checked★ key studySerious infections were 2-3 times more frequent and blood clots about 2 times more frequent after spleen removal.
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?
Splenectomy risks
- How was the study done?
Cohort
- How many people, animals or samples were studied?
8149
- What was actually found?
Higher infections, clots, cancers
- How large was the observed effect?
RR 1.9-3.4 infections
- What do the results mean in everyday life?
Vaccination and prophylaxis are important
- What are the study's limitations?
Confounding by indication
- What does it say about Elawady's specific claim?
Supports infection risk; cancer less certain
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Causation for cancer
-
Infections after spleen removal in Denmark
Thomsen RW et al.. Ann Intern Med 2009 · PMID 19841456 · DOI 10.7326/0003-4819-151-8-200910200-00008Cohort studyindependent cross-checkabstract checked★ key studyPeople without a spleen had more serious infections for years after surgery, although part of the extra risk came from their underlying disease.
Example of a well-supported long-term risk after organ removal.
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?
Measure long-term infection risk after splenectomy
- How was the study done?
National cohort with three comparison groups
- How many people, animals or samples were studied?
3812 Danish patients
- What was actually found?
Infection risk raised early and still 2.5-fold after one year
- How large was the observed effect?
HR 2.5 (>1 year) vs population
- What do the results mean in everyday life?
People without a spleen need vaccinations and fast care for fever
- What are the study's limitations?
Possible surveillance bias
- What does it say about Elawady's specific claim?
Supports the claim
- Do the results apply to Germany and Europe?
Directly applicable
- What can explicitly not be concluded from this study?
Cannot fully separate surgery from disease effects
-
Childhood tonsil surgery and later autoimmune disease in Korea
Chang YS et al.. Front Med (Lausanne) 2026 · PMID 42643288 · DOI 10.3389/fmed.2026.1892240Cohort studyindependent cross-checkabstract checked★ key studyChildren who had the surgery later had about 32% more autoimmune diseases than similar children who did not, but this does not prove the surgery caused them.
Supports the autoimmune association part of the bundled claim.
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?
Check whether childhood tonsil/adenoid surgery is linked to autoimmune disease
- How was the study done?
National cohort
- How many people, animals or samples were studied?
84,030 operated and 336,120 non-operated children
- What was actually found?
Autoimmune disease 86.5 vs 65.3 per 100,000 person-years
- How large was the observed effect?
HR 1.32 (1.23-1.41)
- What do the results mean in everyday life?
Small absolute increase; cause unclear
- What are the study's limitations?
Claims data, residual confounding
- What does it say about Elawady's specific claim?
Supports the association, not proof of causation
- Do the results apply to Germany and Europe?
Moderate
- What can explicitly not be concluded from this study?
Cannot separate surgery from underlying immune tendency
No study in this group is marked as key.
Studies contradicting or limiting the claim (7)
-
Appendix removal and ulcerative colitis
Andersson RE et al.. N Engl J Med 2001 · PMID 11248156 · DOI 10.1056/NEJM200103153441104Cohort studycited by the Tayebat archiveabstract checked★ key studyPeople whose inflamed appendix was removed before age 20 later had less ulcerative colitis; removal for non-inflamed appendix showed no difference.
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?
Immune link
- How was the study done?
Register cohort
- How many people, animals or samples were studied?
212,963
- What was actually found?
Lower UC after inflammatory appendectomy
- How large was the observed effect?
HR 0.58-0.76
- What do the results mean in everyday life?
Appendix/inflammation interacts with gut immunity
- What are the study's limitations?
Observational
- What does it say about Elawady's specific claim?
Does not show harm of removal
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
That the appendix protects health
-
Appendix removal and bowel cancer
Song H et al.. PLoS One 2016 · PMID 26959234 · DOI 10.1371/journal.pone.0151262Cohort studycited by the Tayebat archivefull text, structured risk-of-bias assessmentNo increased risk of stomach, colon or rectal cancer after appendix removal.
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?
Cancer risk
- How was the study done?
Register
- How many people, animals or samples were studied?
480,382
- What was actually found?
No excess
- How large was the observed effect?
SIR EAC 1.32
- What do the results mean in everyday life?
Appendectomy did not raise most GI cancers
- What are the study's limitations?
SIR design
- What does it say about Elawady's specific claim?
Contradicts archive summary
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
Small risks
-
UK: hysterectomy and death risk
Iversen L et al.. BMJ 2005 · PMID 15930026 · DOI 10.1136/bmj.38483.669178.8FCohort studycited by the Tayebat archiveabstract checkedWomen who had a hysterectomy did not die earlier over about 20 years.
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?
Mortality
- How was the study done?
Nested cohort
- How many people, animals or samples were studied?
7410
- What was actually found?
No increase
- How large was the observed effect?
HR 0.94/0.82
- What do the results mean in everyday life?
No mortality penalty found
- What are the study's limitations?
Ovary status unclear
- What does it say about Elawady's specific claim?
Limits claim
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
CVD morbidity
-
Denmark: heart and lung risks after spleen removal
Rørholt M et al.. Haematologica 2017 · PMID 28572164 · DOI 10.3324/haematol.2016.157008Cohort studycited by the Tayebat archiveabstract checkedCompared with patients with the same diseases, only stroke risk stayed higher; heart attack risk was explained by the underlying disease.
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 risk
- How was the study done?
Cohort with disease-matched controls
- How many people, animals or samples were studied?
~70,000
- What was actually found?
Stroke HR 1.56
- How large was the observed effect?
HR 1.56
- What do the results mean in everyday life?
Some but not all risks are due to the operation
- What are the study's limitations?
5 years
- What does it say about Elawady's specific claim?
Limits claim
- Do the results apply to Germany and Europe?
European
- What can explicitly not be concluded from this study?
Long-term
-
Do tonsil and adenoid operations change later infections in children?
Kim JY et al.. Laryngoscope 2021 · PMID 33720418 · DOI 10.1002/lary.29506Cohort studyindependent cross-checkabstract checkedOver 9 years, children who had the operation had the same number of upper airway infections as similar children who did not.
Contradicts the respiratory part of the bundled claim.
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 adenotonsillectomy changes later infections
- How was the study done?
Matched population cohort with equivalence testing
- How many people, animals or samples were studied?
2377 operated Korean children and about 9000 controls
- What was actually found?
No difference in pharyngitis, sinusitis or ear infections
- How large was the observed effect?
Equivalent within ±0.5 visits
- What do the results mean in everyday life?
The operation did not increase later airway infections
- What are the study's limitations?
Claims data; children only
- What does it say about Elawady's specific claim?
Contradicts the claim
- Do the results apply to Germany and Europe?
Moderate
- What can explicitly not be concluded from this study?
Cannot address adulthood
-
Tonsil removal and bowel inflammation: the family test
Bager P et al.. Epidemiology 2019 · PMID 30461527 · DOI 10.1097/EDE.0000000000000946Cohort studyindependent cross-checkabstract checked★ key studyEven relatives of people who had their tonsils out had more Crohn's disease, suggesting shared family factors rather than the surgery itself.
Shows that registry associations after organ removal can reflect confounding.
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?
Test whether the tonsillectomy-IBD link is causal
- How was the study done?
National cohort with family linkage
- How many people, animals or samples were studied?
7 million Danes
- What was actually found?
Higher IBD risk after own and after relatives' tonsillectomy
- How large was the observed effect?
Crohn RR 1.52 (own) and 1.22 (relative)
- What do the results mean in everyday life?
The link is probably partly due to family factors
- What are the study's limitations?
IBD only
- What does it say about Elawady's specific claim?
Contradicts a causal reading of the claim
- Do the results apply to Germany and Europe?
Directly applicable
- What can explicitly not be concluded from this study?
Cannot exclude a small direct effect
-
Genetic test of gallbladder removal and bowel cancer
Chen L et al.. Chin Med J (Engl) 2023 · PMID 37027252 · DOI 10.1097/CM9.0000000000002612Otherindependent cross-checkabstract checkedA genetic analysis found no sign that gallbladder removal itself causes bowel cancer, but gallstone disease might.
Illustrates confounding by the underlying 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?
Use genetics to test causality
- How was the study done?
Mendelian randomisation
- How many people, animals or samples were studied?
Large genetic datasets
- What was actually found?
No causal effect of cholecystectomy on CRC
- How large was the observed effect?
OR 1.54 (0.61-3.92)
- What do the results mean in everyday life?
Gallstones, not the operation, may explain links
- What are the study's limitations?
Weak instruments, wide CIs
- What does it say about Elawady's specific claim?
Contradicts causal claim
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Not definitive
No study in this group is marked as key.
Studies with mixed or unclear results (4)
-
Editorial: gallbladder removal and fatty liver
Nervi F et al.. Am J Gastroenterol 2013 · PMID 23735917 · DOI 10.1038/ajg.2013.84Othercited by the Tayebat archiveabstract checkedA US survey found fatty liver more often in people without a gallbladder; cause unclear.
Does the study support the specific claim? Unclear · Methodological quality: very 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?
Hypothesis
- How was the study done?
Editorial
- How many people, animals or samples were studied?
n/a
- What was actually found?
Association
- How large was the observed effect?
OR 2.4
- What do the results mean in everyday life?
Possible link
- What are the study's limitations?
Cross-sectional
- What does it say about Elawady's specific claim?
Weak
- Do the results apply to Germany and Europe?
Uncertain
- What can explicitly not be concluded from this study?
Causation
-
Gut bacteria overgrowth after gallbladder removal
Sung HJ et al.. J Neurogastroenterol Motil 2015 · PMID 26351251 · DOI 10.5056/jnm15020Cross-sectional studycited by the Tayebat archiveabstract checkedBreath tests were positive more often in symptomatic patients after gallbladder removal.
Does the study support the specific claim? Partly · 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?
SIBO
- How was the study done?
Cross-sectional
- How many people, animals or samples were studied?
237
- What was actually found?
More SIBO
- How large was the observed effect?
46.8% vs 13.3%
- What do the results mean in everyday life?
Possible cause of symptoms
- What are the study's limitations?
Small, selected
- What does it say about Elawady's specific claim?
Weak support
- Do the results apply to Germany and Europe?
Low
- What can explicitly not be concluded from this study?
Incidence in all patients
-
Why some people on thyroid hormone still feel unwell
Perros P et al.. Clin Endocrinol (Oxf) 2023 · PMID 33783849 · DOI 10.1111/cen.14473Narrative reviewcited by the Tayebat archiveabstract checkedA minority keep symptoms despite normal blood tests; causes are debated.
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?
Hypothesis review
- How was the study done?
Narrative
- How many people, animals or samples were studied?
n/a
- What was actually found?
Multiple hypotheses
- How large was the observed effect?
n/a
- What do the results mean in everyday life?
Replacement is not perfect for everyone
- What are the study's limitations?
Narrative
- What does it say about Elawady's specific claim?
Indirect
- Do the results apply to Germany and Europe?
Applicable
- What can explicitly not be concluded from this study?
Effect of thyroidectomy
-
Removing ovaries at hysterectomy and long-term survival
Cusimano MC et al.. BMJ 2021 · PMID 34880044 · DOI 10.1136/bmj-2021-067528Cohort studyindependent cross-checkfull text checked★ key studyRemoving both ovaries before age 50 was linked to more deaths over 20 years (about 1 extra death per 71 women under 45), but not after 50.
Age-dependent long-term mortality excess after ovary removal.
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?
Check whether ovary removal at hysterectomy affects survival
- How was the study done?
Population cohort with propensity weighting
- How many people, animals or samples were studied?
200,549 Ontario women
- What was actually found?
Higher mortality under 50, not over 50
- How large was the observed effect?
HR 1.31 (<45), NNH 71 at 20 y
- What do the results mean in everyday life?
Keeping healthy ovaries matters mainly before menopause
- What are the study's limitations?
Observational; some confounders missing
- What does it say about Elawady's specific claim?
Supports the claim with an age condition; contradicts its size
- 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
Most cited cohorts are Scandinavian (Denmark, Sweden) and directly European; RCTs from the UK and Finland are directly transferable. Guidelines in Europe also emphasize defined indications (not verified here in detail).
Egypt
No Egypt-specific data on rates or outcomes of tonsillectomy, cholecystectomy, hysterectomy, splenectomy or thyroid surgery were identified in this review.
What applies in my country?
General scientific assessment
Potentially true Some long-term risks are real; many associations are not proven to be caused by surgery.
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
- Association of Long-Term Risk of Respiratory, Allergic, and Infectious Diseases With Removal of Adenoids and Tonsils in Childhood.. Byars SG et al.. JAMA Otolaryngol Head Neck Surg 2018 · PMID 29879264 · DOI 10.1001/jamaoto.2018.0614
- Tonsillectomy associated with an increased risk of autoimmune diseases: A national cohort study.. Ji J et al.. J Autoimmun 2016 · PMID 27344241 · DOI 10.1016/j.jaut.2016.06.007
- Intestinal cancer after cholecystectomy: is bile involved in carcinogenesis?. Lagergren J et al.. Gastroenterology 2001 · PMID 11522737 · DOI 10.1053/gast.2001.27083
- Hysterectomy and risk of cardiovascular disease: a population-based cohort study.. Ingelsson E et al.. Eur Heart J 2011 · PMID 21186237 · DOI 10.1093/eurheartj/ehq477
- Cardiovascular and metabolic morbidity after hysterectomy with ovarian conservation: a cohort study.. Laughlin-Tommaso SK et al.. Menopause 2018 · PMID 29286988 · DOI 10.1097/GME.0000000000001043
- Long-term mortality associated with oophorectomy compared with ovarian conservation in the nurses' health study.. Parker WH et al.. Obstet Gynecol 2013 · PMID 23635669 · DOI 10.1097/AOG.0b013e3182864350
- Increased risk of cognitive impairment or dementia in women who underwent oophorectomy before menopause.. Rocca WA et al.. Neurology 2007 · PMID 17761551 · DOI 10.1212/01.wnl.0000276984.19542.e6
- Accelerated Accumulation of Multimorbidity After Bilateral Oophorectomy: A Population-Based Cohort Study.. Rocca WA et al.. Mayo Clin Proc 2016 · PMID 27693001 · DOI 10.1016/j.mayocp.2016.08.002
- Long-term risks after splenectomy among 8,149 cancer-free American veterans: a cohort study with up to 27 years follow-up.. Kristinsson SY et al.. Haematologica 2014 · PMID 24056815 · DOI 10.3324/haematol.2013.092460
- Risk for hospital contact with infection in patients with splenectomy: a population-based cohort study.. Thomsen RW et al.. Ann Intern Med 2009 · PMID 19841456 · DOI 10.7326/0003-4819-151-8-200910200-00008
- Association between childhood tonsillectomy and increased risk of autoimmune disease: a nationwide population-based cohort study.. Chang YS et al.. Front Med (Lausanne) 2026 · PMID 42643288 · DOI 10.3389/fmed.2026.1892240
- Appendectomy and protection against ulcerative colitis.. Andersson RE et al.. N Engl J Med 2001 · PMID 11248156 · DOI 10.1056/NEJM200103153441104
- Risk of Gastrointestinal Cancers among Patients with Appendectomy: A Large-Scale Swedish Register-Based Cohort Study during 1970-2009.. Song H et al.. PLoS One 2016 · PMID 26959234 · DOI 10.1371/journal.pone.0151262
- Long term effects of hysterectomy on mortality: nested cohort study.. Iversen L et al.. BMJ 2005 · PMID 15930026 · DOI 10.1136/bmj.38483.669178.8F
- Risk of cardiovascular events and pulmonary hypertension following splenectomy - a Danish population-based cohort study from 1996-2012.. Rørholt M et al.. Haematologica 2017 · PMID 28572164 · DOI 10.3324/haematol.2016.157008
- Adenotonsillectomy Does not Alter the Risk of Upper Airway Infections in Children.. Kim JY et al.. Laryngoscope 2021 · PMID 33720418 · DOI 10.1002/lary.29506
- Increased Risk of Inflammatory Bowel Disease in Families with Tonsillectomy: A Danish National Cohort Study.. Bager P et al.. Epidemiology 2019 · PMID 30461527 · DOI 10.1097/EDE.0000000000000946
- Associations of cholecystectomy with the risk of colorectal cancer: a Mendelian randomization study.. Chen L et al.. Chin Med J (Engl) 2023 · PMID 37027252 · DOI 10.1097/CM9.0000000000002612
- Cholecystectomy and NAFLD: does gallbladder removal have metabolic consequences?. Nervi F et al.. Am J Gastroenterol 2013 · PMID 23735917 · DOI 10.1038/ajg.2013.84
- Small Intestinal Bacterial Overgrowth Diagnosed by Glucose Hydrogen Breath Test in Post-cholecystectomy Patients.. Sung HJ et al.. J Neurogastroenterol Motil 2015 · PMID 26351251 · DOI 10.5056/jnm15020
- The enigma of persistent symptoms in hypothyroid patients treated with levothyroxine: A narrative review.. Perros P et al.. Clin Endocrinol (Oxf) 2023 · PMID 33783849 · DOI 10.1111/cen.14473
- Association of bilateral salpingo-oophorectomy with all cause and cause specific mortality: population based cohort study.. Cusimano MC et al.. BMJ 2021 · PMID 34880044 · DOI 10.1136/bmj-2021-067528