Nezam El-Tayebat Fact CheckA scientific assessment of the “نظام الطيبات” nutrition system
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Potentially true Certainty of evidence: low provisional C-SOD-07

Artificial sweeteners disturb the beneficial gut bacteria and thereby induce glucose intolerance in animals and humans.

Conclusion: Some sweeteners can alter gut bacteria and short-term glucose responses in some people; long-term harm is unproven.
  1. Original statement
  2. Scientific assessment
  3. In plain language
  4. Studies on this claim
  5. Regional context
  6. What applies in my country?
  7. References

Original statement

ومحلِّيات صناعية تُخل بالبكتيريا النافعة ... والسبب جزئياً أن المحلِّيات الصناعية — كما أوضحت دراسة Nature عام 2014 — تُحدث خللاً في بكتيريا الأمعاء يقود إلى عدم تحمُّل الجلوكوز.

verbatim according to source. Translation by the project; the Arabic wording is authoritative.

Translation

Artificial sweeteners disturb the beneficial gut bacteria and thereby induce glucose intolerance in animals and humans.

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

Microbiome alteration.

Claimed health effect

Glucose intolerance.

Population concerned

General population

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?

Sweeteners damage gut bacteria and cause glucose intolerance.

2. What is demonstrably correct?

Suez 2014 (A-SOD-09) showed microbiome-dependent glucose intolerance in mice and reported similar effects in healthy humans; Suez 2022 RCT (I-SOD-03) found saccharin and sucralose impaired glycaemic responses and each sweetener altered the microbiome.

3. What is wrong or exaggerated?

Not all sweeteners behaved the same: in 2022, aspartame and stevia did not significantly impair glycaemic responses. Effects were person-specific and short-term. The 2014 human data were a small add-on to mouse work.

4. What remains unclear?

Long-term clinical consequences (e.g., diabetes incidence) are not established.

5. Which studies support it?

A-SOD-09, A-UPF-17, I-SOD-03.

6. Which studies contradict it?

I-SOD-03 (no significant glycaemic effect for aspartame and stevia).

7. What applies to Germany and Europe?

Sweeteners are authorised in the EU under Reg. (EC) 1333/2008 with ADIs; WHO 2023 advises against NSS use for weight control (conditional).

8. What is known about Egypt?

No Egypt-specific data.

9. What practical conclusion is appropriate?

Evidence supports caution and further research rather than certainty of harm.

Assessment details

Rationale for certainty of evidence

Mouse experiments with faecal transfer plus a small human component (2014) and a 120-person RCT (2022) showing that saccharin and sucralose, but not aspartame or stevia, impaired glycaemic responses in a person-specific way over 2 weeks. Clinical relevance and long-term effects are unknown.

Source quality

Archive accurately summarises the 2014 abstract but generalises to all sweeteners and to humans 'alike'.

Regional transferability

High (mechanism not region-specific).

Individual exceptions

Effects appear person-specific; not all people respond.

Regional scope of the claim
general (biological/medical)
Last reviewed
25 October 2026 provisional

In plain language

Experiments in mice and a small group of people suggested that some sweeteners change gut bacteria and blood sugar control. A larger 2022 trial confirmed changes for saccharin and sucralose but not for aspartame or stevia, and the effects differed between people. Whether this leads to disease in the long run is not known.

Studies on this claim

Studies supporting the claim (2)

  • Sweeteners, gut bacteria and blood sugar

    Suez J et al.. Nature 2014 · PMID 25231862 · DOI 10.1038/nature13793
    Animal studycited by the Tayebat archiveabstract only checked★ key study

    In mice, sweeteners changed gut bacteria and caused glucose intolerance; a small human test showed similar effects.

    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?

    Do non-caloric artificial sweeteners alter glucose tolerance via the microbiota?

    How was the study done?

    Mouse experiments (antibiotics, faecal transplants into germ-free mice) plus human observational/intervention data.

    How many people, animals or samples were studied?

    Not stated in abstract; Mice; healthy human subjects

    What was actually found?

    NAS induced glucose intolerance via microbiota; abrogated by antibiotics; transferable via faecal transplant; similar dysbiosis and glucose intolerance demonstrated in healthy human subjects.

    How large was the observed effect?

    Not applicable

    What do the results mean in everyday life?

    Some sweeteners may affect blood sugar via gut bacteria.

    What are the study's limitations?

    Human data small (size not in abstract); Commercial formulations contained glucose fillers (not in abstract); Short-term

    What does it say about Elawady's specific claim?

    Mechanistic support for C-SOD-07.

    Do the results apply to Germany and Europe?

    High.

    What can explicitly not be concluded from this study?

    That diet soda causes diabetes, stroke or dementia.

    Scientific details →

  • Sweeteners and gut bacteria (duplicate)

    Suez J et al.. Nature 2014 · PMID 25231862 · DOI 10.1038/nature13793
    Animal studycited by the Tayebat archiveabstract only checked

    Same paper as A-SOD-09.

    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?

    See A-SOD-09.

    How was the study done?

    Same publication as A-SOD-09 (listed twice by the archive).

    How many people, animals or samples were studied?

    Not stated in abstract; Mice; healthy humans

    What was actually found?

    See A-SOD-09.

    How large was the observed effect?

    Not applicable

    What do the results mean in everyday life?

    See A-SOD-09.

    What are the study's limitations?

    Duplicate of A-SOD-09

    What does it say about Elawady's specific claim?

    Supports C-SOD-07 (duplicate).

    Do the results apply to Germany and Europe?

    High.

    What can explicitly not be concluded from this study?

    See A-SOD-09.

    Scientific details →

Studies contradicting or limiting the claim (0)

No studies in this group.

Studies with mixed or unclear results (1)

  • Sweeteners and blood sugar: a 120-person trial

    Suez J et al.. Cell 2022 · PMID 35987213 · DOI 10.1016/j.cell.2022.07.016
    Randomised controlled trialindependent cross-checkabstract only checked★ key study

    Saccharin and sucralose worsened glucose responses in some people; aspartame and stevia did not significantly.

    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?

    Do NNS causally affect human microbiome and glycaemic responses?

    How was the study done?

    Randomized controlled trial (2 weeks) plus gnotobiotic mouse transfer.

    How many people, animals or samples were studied?

    120; Healthy adults

    What was actually found?

    Each NNS distinctly altered stool and oral microbiome and plasma metabolome; saccharin and sucralose significantly impaired glycaemic responses; responder-specific effects reproduced in mice.

    How large was the observed effect?

    Qualitative (numbers not in abstract)

    What do the results mean in everyday life?

    Some sweeteners affect some people.

    What are the study's limitations?

    Short (2 weeks); Clinical relevance unknown; Authors' commercial interests

    What does it say about Elawady's specific claim?

    Mixed for C-SOD-07.

    Do the results apply to Germany and Europe?

    High.

    What can explicitly not be concluded from this study?

    Long-term disease risk.

    Scientific details →

Regional context

Germany / EU

Sweeteners are authorised in the EU under Reg. (EC) 1333/2008 with ADIs; WHO 2023 advises against NSS use for weight control (conditional).

Egypt

No Egypt-specific data.

What applies in my country?

General scientific assessment

Potentially true Some sweeteners can alter gut bacteria and short-term glucose responses in some people; long-term harm is unproven.

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.

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References

  1. Artificial sweeteners induce glucose intolerance by altering the gut microbiota.. Suez J et al.. Nature 2014 · PMID 25231862 · DOI 10.1038/nature13793
  2. Artificial sweeteners induce glucose intolerance by altering the gut microbiota.. Suez J et al.. Nature 2014 · PMID 25231862 · DOI 10.1038/nature13793
  3. Personalized microbiome-driven effects of non-nutritive sweeteners on human glucose tolerance.. Suez J et al.. Cell 2022 · PMID 35987213 · DOI 10.1016/j.cell.2022.07.016

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