Nezam El-Tayebat Fact CheckA scientific assessment of the “نظام الطيبات” nutrition system
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Mostly false Scientifically refuted Certainty of evidence: high provisional C-FAST-03

Rising blood glucose and acetone (ketones) during fasting are evidence that the liver is working properly, not a danger; high glucose plus acetone is not insulin deficiency.

Safety note: High blood glucose together with ketones (acetone) in urine or blood, especially with nausea, vomiting, abdominal pain, rapid breathing, thirst or drowsiness, can mean diabetic ketoacidosis, a medical emergency. In people taking SGLT2 inhibitors (e.g. dapagliflozin/Forxiga, empagliflozin) ketoacidosis can occur with normal or only mildly raised glucose. Seek emergency care; do not wait or fast it out. People with diabetes who wish to fast should do so only after individual risk assessment (IDF-DAR guidelines) and must break the fast if glucose is very high (for example above 300 mg/dL) or low (below 70 mg/dL), or if ketones are present.
In short: This claim is mostly false and dangerous for people with diabetes. Ketones during fasting are normal in healthy people, but in healthy fasting blood glucose falls rather than rises, and high glucose together with ketones is the typical sign of insulin deficiency (ketoacidosis), a medical emergency.
Conclusion: Mostly false and dangerous for people with diabetes: in healthy fasting, glucose falls and ketones rise moderately; high glucose plus ketones signals insulin deficiency, an emergency.
  1. Original statement
  2. Scientific assessment
  3. Scientific evidence in detail
  4. In plain language
  5. Studies on this claim
  6. Regional context
  7. What applies in my country?
  8. References

Original statement

ارتفاع السكر والأسيتون في الصيام، بنظره، دليل عمل الكبد لا خطر.

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

Translation

Rising blood glucose and acetone (ketones) during fasting are evidence that the liver is working properly, not a danger; high glucose plus acetone is not insulin deficiency.

Origin

Source status
Archive editors
Attribution
Archive editors summarising Elawady's view (homepage summary; not the quote box)
Origin
https://eltayebat.com/
Attribution uncertainty
Homepage summary written by the archive operators describing Elawady's views; partly cites his 'statement of the theory' video (aEbRfVSJIOw), otherwise no video reference.
Claimed mechanism

Glucose and ketones are liver products made under stress hormones; their rise shows intact liver mitochondria.

Claimed health effect

Reassurance about high glucose and ketones

Population concerned

Everyone, including people with diabetes

Geographic restriction by Elawady

none found

Diverging source versions

Source status
Video transcript (own words)
Attribution
Elawady (machine transcript)
Video
حدوته السكر والأسيتو وإزاي خوفوك من الأسيتون وهو تصنيع كبدك بالكامل #ضياء_العوضي (Open source)
Published
23 December 2025
Timestamp
not available (transcript has no timings)
Attribution uncertainty
Archive transcript (YouTube CC or AI-generated); no timestamps; 'published' is the date listed by the archive and may be the upload date. Live-stream transcripts can contain viewer comments read aloud; the quoted passage was checked in context to be spoken by Elawady.
Source status
Video transcript (own words)
Attribution
Elawady (machine transcript)
Video
ارتفاع السكر والأسيتون ؟خطر والا ده الطبيعي ؟#ضياء_العوضي (Open source)
Published
23 December 2025
Timestamp
not available (transcript has no timings)
Attribution uncertainty
Archive transcript (YouTube CC or AI-generated); no timestamps; 'published' is the date listed by the archive and may be the upload date. Live-stream transcripts can contain viewer comments read aloud; the quoted passage was checked in context to be spoken by Elawady.
Source status
Video transcript (own words)
Attribution
Elawady (machine transcript)
Video
انت كبني آدم المفروض تاكل إيه ؟ #ضياء_العوضي (Open source)
Published
3 January 2026
Timestamp
not available (transcript has no timings)
Attribution uncertainty
Archive transcript (YouTube CC or AI-generated); no timestamps; 'published' is the date listed by the archive and may be the upload date. Live-stream transcripts can contain viewer comments read aloud; the quoted passage was checked in context to be spoken by Elawady.

Scientific assessment

Mostly false – Essential parts of the statement are not supported by the evidence or are strongly exaggerated.

Certainty of evidence: high – Further research is very unlikely to change the assessment.

1. What was claimed?

High glucose and acetone during fasting show healthy liver function and are not dangerous.

2. What is demonstrably correct?

In prolonged fasting, the liver makes ketone bodies from fat; beta-hydroxybutyrate becomes a key fuel for the brain and allows survival in starvation (I-FAST-01). Starvation ketosis is a recognised, usually mild state; the 2024 consensus distinguishes it from DKA by dietary history (I-INS-07). Stress hormones (cortisol, adrenaline, glucagon) do raise glucose and ketones.

3. What is wrong or exaggerated?

In healthy people fasting glucose does not rise to high levels; it stays in the normal range or falls. High glucose plus ketones and acidosis is the defining triad of DKA (I-INS-08); beta-hydroxybutyrate >=3.0 mmol/L correlates with acidosis and is used for diagnosis (I-INS-07). DKA results from insulin deficiency and is life-threatening without insulin and fluids (I-INS-07). SGLT2 inhibitors cause euglycaemic DKA (I-ODD-10, I-ODD-09). People with diabetes who fast (e.g. Ramadan) have higher rates of severe hypoglycaemia and, in type 1 diabetes, hyperglycaemic complications (I-FAST-10); guidelines therefore require risk stratification and monitoring (I-FAST-11, I-INS-10).

4. What remains unclear?

How often people following the system interpret rising glucose and ketones as harmless, and how many have developed ketoacidosis as a result, is unknown; no data were found.

5. Which studies support it?

I-FAST-01 (fasting ketosis is physiological).

6. Which studies contradict it?

I-INS-07, I-INS-08, I-ODD-09, I-ODD-10, I-FAST-10, I-FAST-11, I-INS-10; IDF-DAR 2021 full guideline: break the fast if glucose >300 mg/dL or <70 mg/dL (I-FAST-108); healthy fasters' glucose stabilised at 4.7 mmol/L (I-FAST-111); type 1 diabetes and Ramadan: more complications and ER visits in high-risk adults (I-FAST-109) and frequent hypoglycaemia with some DKA in adolescents (I-FAST-110).

7. What applies to Germany and Europe?

Same emergency criteria apply.

8. What is known about Egypt?

Many people with diabetes in Egypt fast during Ramadan. The IDF-DAR 2021 guideline, co-authored by Egyptian diabetologists, states that all individuals should break the fast if blood glucose is below 70 mg/dL or above 300 mg/dL, or with symptoms of hypoglycaemia or acute illness (I-FAST-108).

9. What practical conclusion is appropriate?

In healthy people, some ketones during fasting are normal. In people with diabetes, especially type 1 diabetes, insulin users and SGLT2 inhibitor users, high glucose and/or ketones during fasting are a warning sign that requires measurement and medical action.

Assessment details

Rationale for certainty of evidence

Physiological fasting ketosis in healthy people is real (correct kernel), but in healthy people fasting glucose falls or stays normal, it does not rise markedly. The combination of high glucose and high ketones is the definition of diabetic ketoacidosis, an emergency caused by insulin deficiency (consensus). In SGLT2 users ketoacidosis can occur with near-normal glucose. High certainty for the danger in people with diabetes.

Source quality

Homepage editorial plus several own-word videos (one titled about acetone being 'your liver's production').

Regional transferability

Universal.

Individual exceptions

Healthy non-diabetic adults: mild-moderate ketosis after 1-3 days of fasting is expected and usually harmless (pregnancy, children and certain metabolic disorders excepted).

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

Scientific evidence in detail

Scientifically refuted – High-quality evidence shows the opposite, or the claim contradicts well-established physiology.

Research question: During fasting, are rising blood glucose together with ketones a sign of normal liver function rather than insulin deficiency, in healthy people and in people with diabetes?

Research question in detail (PECO)
Population
Healthy fasting adults; people with diabetes (T1D, insulin-treated T2D, SGLT2 inhibitor users) who fast
Intervention or exposure
Fasting (incl. Ramadan, multi-day)
Comparison
Fed state / non-fasting
Geographic scope
universal biology; Ramadan context (Egypt, Arab region)
Outcomes
  • Blood glucose course
  • Ketones
  • DKA, hyperglycaemic emergencies, ER visits

Study results as reported by the authors. Our assessment follows below.

What speaks for the claim?

  • How the body fuels itself during starvation

    Cahill GF. Annu Rev Nutr 2006 · PMID 16848698 · DOI 10.1146/annurev.nutr.26.061505.111258 Narrative reviewabstract checked

    Fasting ketosis is physiological: the liver makes ketones that fuel the brain in starvation.

    Actual result
    Narrative; no numbers.
    Methodological quality
    low (narrative review)
    Relevance
    direct for 'ketones in fasting are normal'
    Limitations
    Does not address high glucose.

    Original publication

  • Insulin after a 36-hour fast

    Jørgensen SW et al.. Am J Physiol Endocrinol Metab 2021 · PMID 33284087 · DOI 10.1152/ajpendo.00433.2020 Otherabstract checkednewly added

    Prolonged fasting produces a physiological, reversible whole-body insulin resistance.

    Actual result
    Increased whole-body insulin resistance after 36 h; higher insulin at refeeding.
    Methodological quality
    moderate (n=13)
    Relevance
    partial: explains a kernel, but fasting glucose itself was not reported to rise to high levels
    Limitations
    Small; abstract only.

    Original publication

What speaks against the claim?

  • Safety of medically supervised multi-day fasting

    Wilhelmi de Toledo F et al.. PLoS One 2019 · PMID 30601864 · DOI 10.1371/journal.pone.0209353 Cohort studyfull text checkednewly added

    In 1,422 non-diabetic people fasting 4-21 days, glucose fell and stabilised at 4.7 mmol/L while ketones rose.

    Actual result
    Glucose 4.7 mmol/L (about 85 mg/dL), p<0.001; ketones increased.
    Methodological quality
    low-moderate (large uncontrolled cohort, full text read)
    Relevance
    direct: healthy fasting means low-normal glucose with ketones, not high glucose
    Limitations
    Uncontrolled; COI.

    Original publication

  • International guideline on diabetic ketoacidosis

    Umpierrez GE et al.. Diabetes Care 2024 · PMID 39052901 · DOI 10.2337/dci24-0032 Guideline / position statementfull text checked

    High glucose plus ketones plus acidosis defines DKA, caused by insulin deficiency.

    Actual result
    BHB >=3.0 mmol/L correlates with acidosis; insulin is the cornerstone of treatment.
    Methodological quality
    high (2024 international consensus)
    Relevance
    direct
    Limitations
    Consensus document.

    Original publication

  • Ramadan guidelines for people with diabetes

    International Diabetes Federation and DAR International Alliance (ed. Hassanein M). IDF (Brussels) 2021 Guideline / position statementfull text checkednewly added

    IDF-DAR 2021: everyone with diabetes must break the fast if glucose exceeds 300 mg/dL or falls below 70 mg/dL; T1D is high/very high risk.

    Actual result
    Explicit thresholds; glucose falls in physiological fasting.
    Methodological quality
    moderate (international guideline incl. Egyptian authors; full PDF read)
    Relevance
    direct
    Limitations
    Consensus-based.

    Original publication

What does the overall evidence say?

Editorial assessment based on the studies above – not itself a study result.

Which position is better supported?

In healthy people, fasting lowers glucose to the low-normal range and raises ketones moderately (physiological ketosis). High glucose together with ketones is the hallmark of insulin deficiency (DKA) and is an emergency, especially in type 1 diabetes and with SGLT2 inhibitors (where ketoacidosis can occur at near-normal glucose).

Why some studies weigh more

International consensus and guidelines (I-INS-07, I-INS-10, I-FAST-108) plus large observational data on fasting physiology outweigh the single physiological kernel (fasting insulin resistance).

Is a causal relationship established? Yes, established Insulin deficiency causes DKA (established pathophysiology; reversal with insulin).

Remaining uncertainty

How many followers have delayed care because of this message (no data).

Justified conclusion

Ketones during fasting can be normal in healthy people; high glucose with ketones is not a sign of a healthy liver but a warning sign of insulin deficiency.

Why do studies seem to disagree?

The kernel (physiological fasting insulin resistance and ketosis) and the danger (DKA) concern different populations and glucose levels; they do not truly conflict.

Does this depend on the country?
General biological effects
Universal.
Eating habits
Many people with diabetes in Egypt fast during Ramadan; the IDF-DAR guideline, co-written by Egyptian diabetologists, requires breaking the fast at glucose >300 mg/dL.
Origin of the food
Not applicable.
Contaminants
Not applicable.
National production conditions
Not applicable.
Legal rules
Not applicable.
Actual monitoring data
Regional data (Saudi Arabia) show emergency visits among fasting people with T1D (I-FAST-109); no Egyptian registry data found.

A regional difference that changes the conclusion is not supported by robust data.

Statistical re-check
  • OR interpretation and CI symmetry – OR 0.53 (0.34-0.82) log-symmetric; '47% lower odds' is an odds ratio from self-reported cross-sectional data, not a causal risk reduction. recalculated
  • Unit conversion of fasting glucose – 4.7 mmol/L = about 85 mg/dL (low-normal). recalculated
Certainty of the overall evidence (GRADE, simplified)
Main outcome
Risk of DKA/hyperglycaemic emergency when high glucose plus ketones in fasting people with diabetes are ignored
Starting level
low (observational studies)
Reasons for upgrading
  • large effect and established mechanism (untreated DKA is lethal; insulin reverses it)
  • consistent consensus across guidelines
Result
high

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
  • IDF and DAR International Alliance: Diabetes and Ramadan: Practical Guidelines 2021 (2021) · Original publication
    All individuals should break the fast if blood glucose <70 mg/dL (3.9 mmol/L) or >300 mg/dL (16.7 mmol/L) or with symptoms of hypoglycaemia or acute illness; people with T1DM are high/very high risk; during fasting glucose falls and insulin secretion is suppressed; when glycogen is depleted and insulin is low, fat is converted to ketones.
  • ADA: Standards of Care in Diabetes-2026, Section 6 (Glycemic Goals, Hypoglycemia, and Hyperglycemic Crises) (2026) · Original publication
    Previously verified by the diabetes team (I-INS-10 full text): people on intensive insulin therapy should not stop or hold basal insulin even if not eating; individuals at risk for DKA should measure ketones; consider holding SGLT2 inhibitors when oral intake cannot be maintained. Not re-fetched in this phase (diabetesjournals.org returned 403).
  • ADA/EASD/JBDS/AACE/DTS: Hyperglycemic Crises in Adults With Diabetes: A Consensus Report (I-INS-07) (2024) · Original publication
    Insulin therapy is the cornerstone of DKA management; SGLT2 inhibitors account for most euglycaemic DKA; starvation ketosis distinguished by history.
Search strategy

Documented literature searches for this review (search strings in the original database syntax).

DatabaseDateSearchLooking forHitsIncluded
Europe PMC26 October 2026Ramadan AND ("type 1 diabetes") AND (ketoacidosis OR DKA OR hyperglycaemia OR hyperglycemia) AND ("systematic review" OR "meta-analysis")contradicting evidence241
Europe PMC26 October 2026Ramadan AND diabetes AND (ketoacidosis OR "hyperglycemic emergencies" OR "hospital admissions") AND (Egypt OR Egyptian OR Saudi OR Arab)contradicting evidence328
Web (WebSearch + direct fetch)26 October 2026IDF-DAR Diabetes and Ramadan Practical Guidelines 2021 break the fast glucose 300 mg/dL 70 mg/dL; PDF downloaded from media.idf.org (daralliance.org not resolvable)guidelines10
Europe PMC26 October 2026("prolonged fasting" OR "periodic fasting" OR "water-only fasting" OR "long-term fasting") AND (safety OR "adverse events") AND (subjects OR participants) AND (observational OR "chart review" OR cohort)supporting evidence1199
PubMed26 October 2026("starvation ketosis"[tiab] OR "fasting ketosis"[tiab]) AND (physiological OR benign OR normal)supporting evidence41
PubMed26 October 2026(fasting[ti]) AND (glucose[ti] OR ketone*[ti]) AND healthy AND (days OR prolonged)supporting evidence38
PubMed26 October 2026Ramadan[ti] AND (diabetes[ti]) AND (ketoacidosis OR hyperglycemia OR hyperglycaemia) AND (meta-analysis[pt] OR cohort OR guideline)contradicting evidence22
PubMed26 October 2026(euglycemic[ti] OR euglycaemic[ti]) AND ketoacidosis[ti] AND (fasting OR "SGLT2")contradicting evidence256

Open questions

Case reports of DKA in people following the system (none found).

How deeply was this checked?

13 linked studies: 6 checked in full text (2 of them with a structured risk-of-bias assessment), 7 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
  1. 25 October 2026 · Phase 1 · Initial assessment: Mostly false (high)
  2. 26 October 2026 · Phase 4 (systematic evidence review) · Re-examined with extended evidence; verdict unchanged: Mostly false (high)
    New evidence (IDF-DAR full text, regional T1D Ramadan data, large fasting cohort showing glucose falls) confirms the existing verdict; the correct kernel (fasting ketosis) keeps it at mostly false rather than false.
    New sources: I-FAST-108 I-FAST-109 I-FAST-110 I-FAST-111 I-FAST-102

In plain language

When healthy people fast for a day or more, the liver makes ketones (acetone) from fat, and this is normal. But blood sugar in healthy people does not rise high during fasting. If someone with diabetes has high sugar and ketones together, this can be ketoacidosis, which is an emergency. Telling people with diabetes to ignore these signs can cost lives.

Studies on this claim

Studies supporting the claim (1)

  • How the body fuels itself during starvation

    Cahill GF. Annu Rev Nutr 2006 · PMID 16848698 · DOI 10.1146/annurev.nutr.26.061505.111258
    Narrative reviewindependent cross-checkabstract checked

    During long fasting the brain uses ketones from fat, which allows survival.

    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?

    Fuel metabolism in prolonged starvation

    How was the study done?

    Narrative/biographical review

    How many people, animals or samples were studied?

    not applicable; Humans in starvation (historical studies)

    What was actually found?

    Ketones fuel the brain in starvation.

    How large was the observed effect?

    not reported

    What do the results mean in everyday life?

    Fasting ketosis is normal physiology in healthy people.

    What are the study's limitations?

    Narrative; No quantitative data in abstract

    What does it say about Elawady's specific claim?

    Supports physiological kernels of C-FAST-01, C-FAST-03, C-FAST-04 (fasting ketosis is normal).

    Do the results apply to Germany and Europe?

    Physiology universal.

    What can explicitly not be concluded from this study?

    That high glucose plus ketones is harmless in diabetes.

    Scientific details →

Studies contradicting or limiting the claim (11)

  • International guideline on diabetic ketoacidosis

    Umpierrez GE et al.. Diabetes Care 2024 · PMID 39052901 · DOI 10.2337/dci24-0032
    Guideline / position statementindependent cross-checkfull text checked★ key study

    Insulin, fluids and potassium are the core treatment; with this, fewer than 1% of adults die.

    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?

    Diagnosis and management of DKA and HHS in adults

    How was the study done?

    International consensus report based on systematic examination of literature since 2009 (ADA, EASD, JBDS, AACE, DTS)

    How many people, animals or samples were studied?

    not applicable; Adults with diabetes

    What was actually found?

    Insulin is the cornerstone; glucocorticoids worsen hyperglycaemia.

    How large was the observed effect?

    Mortality <1% with treatment

    What do the results mean in everyday life?

    Ketoacidosis needs hospital treatment with insulin.

    What are the study's limitations?

    Consensus, not trial

    What does it say about Elawady's specific claim?

    Directly contradicts C-INS-08; supports danger in C-FAST-03; contradicts C-INS-07, C-INS-10.

    Do the results apply to Germany and Europe?

    EASD and JBDS (UK) co-authored; directly applicable.

    What can explicitly not be concluded from this study?

    Outcomes of untreated DKA quantitatively.

    Scientific details →

  • Review on diabetic ketoacidosis

    Dhatariya KK et al.. Nat Rev Dis Primers 2020 · PMID 32409703 · DOI 10.1038/s41572-020-0165-1
    Narrative reviewindependent cross-checkfull text, structured risk-of-bias assessment

    DKA is an emergency that can kill; it is treated with fluids, insulin and salts, and insulin must not be stopped in type 1 diabetes even when not eating.

    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?

    Epidemiology, pathogenesis, diagnosis and management of DKA

    How was the study done?

    Narrative expert review (Nature Reviews Disease Primers)

    How many people, animals or samples were studied?

    not applicable; Adults and children with diabetes

    What was actually found?

    DKA is diagnosed by high glucose, ketones and acid; it kills <1% when treated in rich countries but up to 26-41% where treatment is lacking; treatment is fluids, insulin and potassium, and insulin must never be stopped in type 1 diabetes even when not eating.

    How large was the observed effect?

    not applicable

    What do the results mean in everyday life?

    DKA is an emergency.

    What are the study's limitations?

    Narrative expert review without systematic methods; one author has research support from insulin makers.

    What does it say about Elawady's specific claim?

    Contradicts C-INS-08, C-INS-02, C-FAST-01, C-FAST-03.

    Do the results apply to Germany and Europe?

    International.

    What can explicitly not be concluded from this study?

    Quantitative estimates.

    Scientific details →

  • SGLT2 drugs and ketoacidosis

    Douros A et al.. Ann Intern Med 2020 · PMID 32716707 · DOI 10.7326/M20-0289
    Cohort studyindependent cross-checkabstract checked★ key study

    About 2 per 1,000 users per year developed ketoacidosis, nearly 3 times more than with DPP-4 drugs.

    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?

    SGLT2 vs DPP-4 inhibitors and DKA risk

    How was the study done?

    Multicentre population-based cohort (prevalent new-user design, propensity-matched)

    How many people, animals or samples were studied?

    208,757 matched pairs; Type 2 diabetes new users

    What was actually found?

    HR 2.85.

    How large was the observed effect?

    HR 2.85 (1.99-4.08)

    What do the results mean in everyday life?

    Rare but real; caution with fasting/illness.

    What are the study's limitations?

    No lab data; Unmeasured confounding

    What does it say about Elawady's specific claim?

    Supports C-ODD-02; relevant to C-FAST-03.

    Do the results apply to Germany and Europe?

    UK data included.

    What can explicitly not be concluded from this study?

    That the drugs are net harmful.

    Scientific details →

  • Ketoacidosis with normal blood sugar on SGLT2 drugs

    Peters AL et al.. Diabetes Care 2015 · PMID 26078479 · DOI 10.2337/dc15-0843
    Case series / case reportindependent cross-checkfull text, structured risk-of-bias assessment

    Several patients developed ketoacidosis with near-normal sugar, so it was recognised late.

    Does the study support the specific claim? Yes · 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?

    Describe euglycaemic DKA with SGLT2 inhibitors

    How was the study done?

    Case series

    How many people, animals or samples were studied?

    9 individuals, 13 episodes; Patients with T1D or T2D on SGLT2 inhibitors

    What was actually found?

    13 episodes in 9 patients on canagliflozin (7 with off-label type 1 diabetes); glucose often near normal, delaying diagnosis; all recovered with IV fluids and insulin.

    How large was the observed effect?

    not applicable

    What do the results mean in everyday life?

    Check ketones when unwell on SGLT2 drugs.

    What are the study's limitations?

    Incidental case collection, no denominator, mostly off-label type 1 use, all on canagliflozin.

    What does it say about Elawady's specific claim?

    Supports C-ODD-02; key for C-FAST-03 safety.

    Do the results apply to Germany and Europe?

    US.

    What can explicitly not be concluded from this study?

    How often this happens; that every SGLT2 inhibitor (e.g. dapagliflozin) carries the same risk (inferred, not shown here).

    Scientific details →

  • Fasting in Ramadan with diabetes (EPIDIAR)

    Salti I et al.. Diabetes Care 2004 · PMID 15451892 · DOI 10.2337/diacare.27.10.2306
    Cross-sectional studyindependent cross-checkabstract checked★ key study

    Severe low blood sugar was 4.7 times (type 1) and 7.5 times (type 2) more common during Ramadan.

    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?

    Diabetes characteristics and effects of Ramadan fasting

    How was the study done?

    Population-based retrospective cross-sectional survey (EPIDIAR)

    How many people, animals or samples were studied?

    12,243; Muslims with type 1 or type 2 diabetes

    What was actually found?

    Severe hypoglycaemia increased.

    How large was the observed effect?

    0.14 vs 0.03/month (T1D)

    What do the results mean in everyday life?

    People with diabetes need a plan before fasting.

    What are the study's limitations?

    Retrospective, recall

    What does it say about Elawady's specific claim?

    Contradicts safety implications of C-FAST-03, C-FAST-05, C-FAST-07; relevant to C-ODD-11.

    Do the results apply to Germany and Europe?

    Relevant to Muslim communities in Europe.

    What can explicitly not be concluded from this study?

    Mortality effects.

    Scientific details →

  • IDF-DAR Ramadan guidelines 2021

    Hassanein M et al.. Diabetes Res Clin Pract 2022 · PMID 35016991 · DOI 10.1016/j.diabres.2021.109185
    Guideline / position statementindependent cross-checkabstract checked

    People with diabetes who fast need individual risk assessment and medical guidance.

    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?

    Management of diabetes during Ramadan fasting

    How was the study done?

    Practical guideline (IDF and DaR International Alliance)

    How many people, animals or samples were studied?

    not applicable; People with diabetes who fast

    What was actually found?

    Guidance on risk stratification.

    How large was the observed effect?

    not applicable

    What do the results mean in everyday life?

    Fast only with a medical plan.

    What are the study's limitations?

    Abstract only read

    What does it say about Elawady's specific claim?

    Contradicts C-FAST-03 and C-FAST-10 safety implications.

    Do the results apply to Germany and Europe?

    Applicable to fasting Muslims in Europe.

    What can explicitly not be concluded from this study?

    Specific thresholds (not in abstract).

    Scientific details →

  • ADA guideline 2026: blood sugar goals and emergencies

    American Diabetes Association Professional Practice Committee for Diabetes* . Diabetes Care 2026 · PMID 41358894 · DOI 10.2337/dc26-S006
    Guideline / position statementindependent cross-checkfull text checked★ key study

    Most adults should aim for HbA1c below 7%, avoid low sugar, and measure ketones when at risk.

    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?

    Glycaemic goals, hypoglycaemia and hyperglycaemic crises

    How was the study done?

    Clinical practice guideline (ADA Standards of Care 2026, Section 6)

    How many people, animals or samples were studied?

    not applicable; People with diabetes

    What was actually found?

    Individual targets; do not stop basal insulin when not eating.

    How large was the observed effect?

    not applicable

    What do the results mean in everyday life?

    Moderate targets and safety rules.

    What are the study's limitations?

    US-centred; Partially read

    What does it say about Elawady's specific claim?

    Supports C-INS-04, C-INS-11; contradicts C-FAST-01, C-FAST-03, C-DIAB-02.

    Do the results apply to Germany and Europe?

    Consistent with EASD guidance.

    What can explicitly not be concluded from this study?

    Not applicable.

    Scientific details →

  • Ramadan guidelines for people with diabetes

    International Diabetes Federation and DAR International Alliance (ed. Hassanein M). IDF (Brussels) 2021
    Guideline / position statementindependent cross-checkfull text checked★ key study

    People with diabetes who fast must stop fasting if blood sugar goes above 300 mg/dL or below 70 mg/dL.

    Break the fast if glucose >300 mg/dL or <70 mg/dL; T1D is high/very high risk; glucose falls in normal fasting.

    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?

    Give practical advice for safe fasting with diabetes.

    How was the study done?

    International expert guideline.

    How many people, animals or samples were studied?

    not applicable

    What was actually found?

    Risk stratification; break-fast thresholds; T1D high risk.

    How large was the observed effect?

    not applicable

    What do the results mean in everyday life?

    High blood sugar during fasting is a reason to stop fasting and check for danger, not a sign of health.

    What are the study's limitations?

    Consensus-based.

    What does it say about Elawady's specific claim?

    Contradicts the claim for people with diabetes.

    Do the results apply to Germany and Europe?

    Used by clinicians in Egypt and the Gulf and by European diabetes services for Muslim patients.

    What can explicitly not be concluded from this study?

    Precise risk of DKA per fasting day.

    Scientific details →

  • Type 1 diabetes and Ramadan complications

    Alguwaihes AM et al.. Clin Med Insights Endocrinol Diabetes 2025 · PMID 41001082 · DOI 10.1177/11795514251376888
    Cross-sectional studyindependent cross-checkabstract checked★ key study

    Among 963 Saudi adults with type 1 diabetes, those rated high risk had more complications and emergency visits when fasting.

    In 963 adults with T1D, high-risk fasters had more complications and ER visits.

    Does the study support the specific claim? No · 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?

    Test a fasting risk tool.

    How was the study done?

    Online survey after Ramadan 2022.

    How many people, animals or samples were studied?

    963 adults with T1D.

    What was actually found?

    High-risk group: more ER visits; education linked to fewer visits.

    How large was the observed effect?

    OR 0.53 (0.34-0.82) for education.

    What do the results mean in everyday life?

    Fasting with type 1 diabetes can lead to emergencies; preparation with doctors helps.

    What are the study's limitations?

    Self-reported; no lab confirmation.

    What does it say about Elawady's specific claim?

    Contradicts the idea that high sugar during fasting is harmless.

    Do the results apply to Germany and Europe?

    Directly relevant to Arab populations including Egypt.

    What can explicitly not be concluded from this study?

    Exact DKA rates.

    Scientific details →

  • Teenagers with type 1 diabetes fasting Ramadan

    Safari O et al.. BMC Endocr Disord 2025 · PMID 39966830 · DOI 10.1186/s12902-025-01835-1
    Meta-analysisindependent cross-checkabstract checked★ key study

    Low blood sugar was very common and high sugar and ketoacidosis also occurred in fasting teenagers with type 1 diabetes.

    Adolescents with T1D fasting Ramadan: hypoglycaemia 50.79/100 observations; hyperglycaemia and DKA reported.

    Does the study support the specific claim? No · 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?

    Summarise risks of Ramadan fasting for teenagers with T1D.

    How was the study done?

    Meta-analysis of 9 studies.

    How many people, animals or samples were studied?

    458 adolescents.

    What was actually found?

    No change in HbA1c; frequent hypoglycaemia; some hyperglycaemia and DKA.

    How large was the observed effect?

    Hypoglycaemia 50.79/100 observations.

    What do the results mean in everyday life?

    Children with type 1 diabetes need close supervision if they fast.

    What are the study's limitations?

    Small observational studies.

    What does it say about Elawady's specific claim?

    Contradicts a relaxed attitude to high glucose and ketones in fasting people with diabetes.

    Do the results apply to Germany and Europe?

    Relevant to Muslim families in Europe and Egypt.

    What can explicitly not be concluded from this study?

    Exact DKA risk.

    Scientific details →

  • Safety of medically supervised multi-day fasting

    Wilhelmi de Toledo F et al.. PLoS One 2019 · PMID 30601864 · DOI 10.1371/journal.pone.0209353
    Cohort studyindependent cross-checkfull text checked★ key study

    In 1,422 clinic guests, supervised fasting with small amounts of juice and soup was mostly well tolerated; blood sugar fell to the low-normal range.

    In non-diabetic fasters glucose fell and stabilised at 4.7 mmol/L (about 85 mg/dL) while ketones rose.

    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?

    Document safety and changes during Buchinger fasting.

    How was the study done?

    One-year observational study, before-after measurements.

    How many people, animals or samples were studied?

    1,422 adults at a German fasting clinic.

    What was actually found?

    Weight and BP fell; glucose 4.7 mmol/L; ketones rose; adverse effects 0.7%; 2 hospital admissions.

    How large was the observed effect?

    p<0.001 for weight, BP, glucose changes.

    What do the results mean in everyday life?

    Short fasts under medical care with fluids and minimal calories are usually tolerated by selected healthy adults.

    What are the study's limitations?

    No control group; clinic-run study; selected participants.

    What does it say about Elawady's specific claim?

    Does not support 'zero inputs'; contradicts rising glucose as a normal fasting sign.

    Do the results apply to Germany and Europe?

    German setting (Heilfasten); applicable to supervised fasting in Europe.

    What can explicitly not be concluded from this study?

    Long-term health benefits; safety for excluded groups.

    Scientific details →

Studies with mixed or unclear results (1)

  • Insulin after a 36-hour fast

    Jørgensen SW et al.. Am J Physiol Endocrinol Metab 2021 · PMID 33284087 · DOI 10.1152/ajpendo.00433.2020
    Otherindependent cross-checkabstract checked★ key study

    In 13 healthy men, a 36-hour fast only slightly reduced early insulin release; the body became more insulin resistant for a while.

    Prolonged fasting causes a physiological whole-body insulin resistance in healthy people - a real kernel - but this is not hyperglycaemia with ketoacidosis.

    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?

    Understand how insulin release and action change with a longer fast.

    How was the study done?

    Compared 36-h and 12-h fasts with glucose tolerance testing and tracers.

    How many people, animals or samples were studied?

    13 healthy young men in Denmark.

    What was actually found?

    Insulin secretion persisted with a minor reduction; whole-body insulin resistance increased.

    How large was the observed effect?

    Not available (abstract only).

    What do the results mean in everyday life?

    Healthy bodies keep making some insulin even after a day and a half without food.

    What are the study's limitations?

    Tiny sample, men only, short fast.

    What does it say about Elawady's specific claim?

    Insulin does not go to zero; physiological insulin resistance during fasting is real but different from diabetes.

    Do the results apply to Germany and Europe?

    Applies; same physiology.

    What can explicitly not be concluded from this study?

    Effects of fasts longer than 36 h; women; people with diabetes.

    Scientific details →

Regional context

Germany / EU

Same emergency criteria apply.

Egypt

Many people with diabetes in Egypt fast during Ramadan. The IDF-DAR 2021 guideline, co-authored by Egyptian diabetologists, states that all individuals should break the fast if blood glucose is below 70 mg/dL or above 300 mg/dL, or with symptoms of hypoglycaemia or acute illness (I-FAST-108).

What applies in my country?

General scientific assessment

Mostly false Mostly false and dangerous for people with diabetes: in healthy fasting, glucose falls and ketones rise moderately; high glucose plus ketones signals insulin deficiency, an emergency.

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

  1. Fuel metabolism in starvation.. Cahill GF. Annu Rev Nutr 2006 · PMID 16848698 · DOI 10.1146/annurev.nutr.26.061505.111258
  2. Hyperglycemic Crises in Adults With Diabetes: A Consensus Report.. Umpierrez GE et al.. Diabetes Care 2024 · PMID 39052901 · DOI 10.2337/dci24-0032
  3. Diabetic ketoacidosis.. Dhatariya KK et al.. Nat Rev Dis Primers 2020 · PMID 32409703 · DOI 10.1038/s41572-020-0165-1
  4. Sodium-Glucose Cotransporter-2 Inhibitors and the Risk for Diabetic Ketoacidosis : A Multicenter Cohort Study.. Douros A et al.. Ann Intern Med 2020 · PMID 32716707 · DOI 10.7326/M20-0289
  5. Euglycemic Diabetic Ketoacidosis: A Potential Complication of Treatment With Sodium-Glucose Cotransporter 2 Inhibition.. Peters AL et al.. Diabetes Care 2015 · PMID 26078479 · DOI 10.2337/dc15-0843
  6. A population-based study of diabetes and its characteristics during the fasting month of Ramadan in 13 countries: results of the epidemiology of diabetes and Ramadan 1422/2001 (EPIDIAR) study.. Salti I et al.. Diabetes Care 2004 · PMID 15451892 · DOI 10.2337/diacare.27.10.2306
  7. Diabetes and Ramadan: Practical guidelines 2021.. Hassanein M et al.. Diabetes Res Clin Pract 2022 · PMID 35016991 · DOI 10.1016/j.diabres.2021.109185
  8. 6. Glycemic Goals, Hypoglycemia, and Hyperglycemic Crises: Standards of Care in Diabetes-2026.. American Diabetes Association Professional Practice Committee for Diabetes* . Diabetes Care 2026 · PMID 41358894 · DOI 10.2337/dc26-S006
  9. Diabetes and Ramadan: Practical Guidelines 2021 (IDF-DAR), International Diabetes Federation and DAR International Alliance. International Diabetes Federation and DAR International Alliance (ed. Hassanein M). IDF (Brussels) 2021
  10. Assessment of the IDF-DAR Fasting Risk Assessment Tool to Predict Type 1 Diabetes-Related Complications During Ramadan in a Real-World Setting.. Alguwaihes AM et al.. Clin Med Insights Endocrinol Diabetes 2025 · PMID 41001082 · DOI 10.1177/11795514251376888
  11. Ramadan fasting among adolescents with type 1 diabetes: a systematic review and meta-analysis.. Safari O et al.. BMC Endocr Disord 2025 · PMID 39966830 · DOI 10.1186/s12902-025-01835-1
  12. Safety, health improvement and well-being during a 4 to 21-day fasting period in an observational study including 1422 subjects.. Wilhelmi de Toledo F et al.. PLoS One 2019 · PMID 30601864 · DOI 10.1371/journal.pone.0209353
  13. Impact of prolonged fasting on insulin secretion, insulin action, and hepatic versus whole body insulin secretion disposition indices in healthy young males.. Jørgensen SW et al.. Am J Physiol Endocrinol Metab 2021 · PMID 33284087 · DOI 10.1152/ajpendo.00433.2020

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