Antibiotics make people (especially children) gain weight by altering gut bacteria, as they do in fattened poultry; early-childhood antibiotic courses raise obesity risk.
Original statement
المضادات الحيويه بتوزن بتزود الوزن اه لانها بتاثر على المجتمع البكتيري بتاع قولونك وامعائك من الاخر كده فبتخن عشان كده العيال الصغيره لما بتضرب مضادات حيويه جه دور كحه اخد مضاد حيوي ف تلاقي الواد تخن
verbatim according to source. Translation by the project; the Arabic wording is authoritative.
Translation
Antibiotics make people (especially children) gain weight by altering gut bacteria, as they do in fattened poultry; early-childhood antibiotic courses raise obesity risk.
Origin
- Source status
- Video transcript (own words)
- Attribution
- Elawady (machine transcript)
- Video
- Dr Diaa Al Awady د ضياء العوضي is live! مصدر الغذاء الوريد البابي (Open source)
- Published
- 27 July 2025
- Timestamp
- 0:50:11 (location in the original video’s automatic YouTube caption track; confirms where the words occur, not who speaks)
- Attribution uncertainty
- Archive transcript (YouTube CC or AI-generated); wording may contain transcription errors; no timestamps; 'published' is the date listed by the archive. Passage read in context.
- Claimed mechanism
Altered gut microbiota changes energy metabolism (growth-promotion effect known from livestock).
- Claimed health effect
Obesity.
- Population concerned
Children
- Geographic restriction by Elawady
none found
Diverging source versions
والمضادات تسهم في السمنة
- Source status
- Archive quote (no location given)
- Attribution
- Elawady (archive paraphrase; source video not given)
- Origin
- https://eltayebat.com/rule/antibiotic-overuse/
- Attribution uncertainty
- Text in the archive's 'د. ضياء يقول' box; no video reference given by the archive.
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?
Antibiotics cause weight gain via gut bacteria.
2. What is demonstrably correct?
Bailey 2014: >=4 courses before 24 months RR 1.11 (1.02-1.21); broad-spectrum RR 1.16 (1.06-1.29) (A-ABX-01). ALSPAC: exposure before 6 months was associated with slightly higher body mass up to 38 months (BMI z-score +0.067, about 90 g), but not at 7 years, and later exposures were not consistently associated (A-ABX-02). Meta-analyses: OR 1.11 (1.02-1.20) (I-ABX-05); postnatal OR 1.09 (1.05-1.12), 4+ courses OR 1.31 (1.17-1.46), very low certainty (I-ABX-04). Mice: continuous low-dose penicillin in early life caused increased adiposity, transferable via microbiota (A-ABX-03).
3. What is wrong or exaggerated?
Observational associations are small and may be partly due to confounding, including the infections for which antibiotics were given (not controlled in A-ABX-02); Rasmussen et al. state it is 'unclear whether this association is mediated via direct effects of antibiotics on the gut microbiota' (I-ABX-05). The ALSPAC association was transient. The mouse model used continuous sub-therapeutic penicillin (a growth-promoter model, 1 ug/g body weight), unlike human treatment courses; effects were sex-dependent, were lost in males with ageing in the early-limited experiment and disappeared on a second microbiota transfer, and the authors state that human relevance is untested (A-ABX-03). 'You see the boy get fat' is anecdotal.
4. What remains unclear?
Causality in humans.
5. Which studies support it?
A-ABX-01, I-ABX-05; A-ABX-03 (mechanistic plausibility only, mouse growth-promoter model); partly A-ABX-02 (small, transient association) and I-ABX-04.
6. Which studies contradict it?
I-ABX-04 (certainty very low).
7. What applies to Germany and Europe?
Cohort data come from the US and the UK (ALSPAC) (A-ABX-01, A-ABX-02); the meta-analyses pooled international studies (I-ABX-04, I-ABX-05).
8. What is known about Egypt?
No Egyptian data were reviewed.
9. What practical conclusion is appropriate?
Avoid unnecessary antibiotics in infants; necessary treatment should not be withheld for fear of weight gain.
Assessment details
- Rationale for certainty of evidence
Consistent small associations (OR about 1.1, up to 1.3 for 4+ courses) in observational studies; a 2023 meta-analysis rates certainty as very low; mouse experiments show a causal microbiota pathway; residual confounding (infections, socio-economic factors) is likely.
- Source quality
Elawady's statement is a strong causal claim; archive cites the best available data accurately.
- Regional transferability
Moderate.
- Individual exceptions
Effect per child is small; many children receive antibiotics without becoming obese.
- Regional scope of the claim
- general (biological/medical)
- Last reviewed
- 25 October 2026 provisional
In plain language
Studies of many children found that those who received several antibiotic courses as babies were slightly more likely to be overweight later, by around 10%. Mouse studies show that changes in gut bacteria can cause weight gain. In humans it is not proven that antibiotics are the cause, because sick children differ in other ways too. The effect, if real, is small.
Studies on this claim
Studies supporting the claim (3)
-
Antibiotics in infancy and childhood obesity
Bailey LC et al.. JAMA Pediatr 2014 · PMID 25265089 · DOI 10.1001/jamapediatrics.2014.1539Cohort studycited by the Tayebat archiveabstract only checked★ key studyChildren with 4+ antibiotic courses before age 2 were about 11% more likely to be obese.
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?
Link antibiotics to obesity.
- How was the study done?
Health-record cohort.
- How many people, animals or samples were studied?
64,580 children.
- What was actually found?
Small increased risk with broad-spectrum.
- How large was the observed effect?
RR 1.11-1.16.
- What do the results mean in everyday life?
Small effect, may not be causal.
- 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?
Moderate.
- What can explicitly not be concluded from this study?
Causation.
-
Antibiotics, gut bacteria and fat in mice
Cox LM et al.. Cell 2014 · PMID 25126780 · DOI 10.1016/j.cell.2014.05.052Animal studycited by the Tayebat archivefull text checked★ key studyLow-dose penicillin early in life made mice fatter via their gut bacteria.
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?
Test causality in mice.
- How was the study done?
Experiments, microbiota transfer.
- How many people, animals or samples were studied?
Mouse groups of about 3-10 animals per experiment.
- What was actually found?
Continuous low-dose penicillin early in life increased weight and fat in mice (effects differed by sex); germ-free mice given the altered gut bacteria gained fat faster.
- What do the results mean in everyday life?
Shows a plausible mechanism.
- What are the study's limitations?
Mouse model; tiny groups and many tests; continuous low dosing like farm growth promoters, unlike human treatment courses; effects inconsistent between sexes.
- What does it say about Elawady's specific claim?
Mechanism only.
- What can explicitly not be concluded from this study?
Human effect.
-
Infant antibiotics and overweight (meta-analysis 2018)
Rasmussen SH et al.. Diabetes Obes Metab 2018 · PMID 29359849 · DOI 10.1111/dom.13230Meta-analysisindependent cross-checkabstract only checkedSlightly higher risk, mainly with repeated or very early treatment.
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?
Pool studies.
- How was the study done?
Meta-analysis.
- How many people, animals or samples were studied?
13 studies.
- What was actually found?
Small association.
- How large was the observed effect?
OR 1.11.
- What do the results mean in everyday life?
Small.
- 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?
Moderate.
- What can explicitly not be concluded from this study?
Mechanism.
No study in this group is marked as key.
Studies contradicting or limiting the claim (0)
No studies in this group.
Studies with mixed or unclear results (2)
-
Early antibiotics and childhood overweight (meta-analysis 2023)
Chagas AP et al.. Obes Res Clin Pract 2023 · PMID 37573229 · DOI 10.1016/j.orcp.2023.07.001Meta-analysisindependent cross-checkabstract only checked★ key studyA small association (about 9-10% higher odds) was found, but certainty was very low.
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?
Pool cohort studies.
- How was the study done?
Meta-analysis.
- How many people, animals or samples were studied?
42 studies.
- What was actually found?
Small association.
- How large was the observed effect?
OR 1.09; 4+ courses 1.31.
- What do the results mean in everyday life?
Possible small effect.
- What are the study's limitations?
Very low certainty.
- What does it say about Elawady's specific claim?
Weakly supports.
- Do the results apply to Germany and Europe?
Moderate.
- What can explicitly not be concluded from this study?
Causation.
-
Infant antibiotics and body mass (UK)
Trasande L et al.. Int J Obes (Lond) 2013 · PMID 22907693 · DOI 10.1038/ijo.2012.132Cohort studycited by the Tayebat archivefull text checkedAntibiotics before 6 months were linked to slightly higher body mass 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?
Link antibiotics to weight.
- How was the study done?
Birth cohort.
- How many people, animals or samples were studied?
11,532.
- What was actually found?
Antibiotics before 6 months: body mass slightly higher at 10-38 months (+0.07 to +0.1 SD), overweight odds 1.22 at 38 months; no clear effect at 7 years; later exposures not consistently linked.
- How large was the observed effect?
+0.067 SD BMI at 38 months, about 90 g; overweight OR 1.22.
- What do the results mean in everyday life?
Small.
- What are the study's limitations?
Parent-reported antibiotics; infections themselves not accounted for; effect not seen at 7 years; many comparisons.
- What does it say about Elawady's specific claim?
Supports association.
- Do the results apply to Germany and Europe?
High.
- What can explicitly not be concluded from this study?
Causation, or a lasting effect on obesity beyond early childhood.
No study in this group is marked as key.
Regional context
Germany / EU
Cohort data come from the US and the UK (ALSPAC) (A-ABX-01, A-ABX-02); the meta-analyses pooled international studies (I-ABX-04, I-ABX-05).
Egypt
No Egyptian data were reviewed.
What applies in my country?
General scientific assessment
Potentially true Plausible with a small, consistent association, but human causation is not established.
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 antibiotics in infancy with early childhood obesity.. Bailey LC et al.. JAMA Pediatr 2014 · PMID 25265089 · DOI 10.1001/jamapediatrics.2014.1539
- Altering the intestinal microbiota during a critical developmental window has lasting metabolic consequences.. Cox LM et al.. Cell 2014 · PMID 25126780 · DOI 10.1016/j.cell.2014.05.052
- Antibiotic exposure in early life and childhood overweight and obesity: A systematic review and meta-analysis.. Rasmussen SH et al.. Diabetes Obes Metab 2018 · PMID 29359849 · DOI 10.1111/dom.13230
- Early-life exposure to antibiotics and excess body weight in childhood and adolescence: A systematic review and meta-analysis.. Chagas AP et al.. Obes Res Clin Pract 2023 · PMID 37573229 · DOI 10.1016/j.orcp.2023.07.001
- Infant antibiotic exposures and early-life body mass.. Trasande L et al.. Int J Obes (Lond) 2013 · PMID 22907693 · DOI 10.1038/ijo.2012.132