Animal studycited by the Tayebat archiveabstract only checked A-VEG-05 standard review
Oxalate precursor and kidney crystals in rats
Dietary oxalate and calcium oxalate nephrolithiasis.
Overview
Khan SR et al.. J Urol 2007 · PMID 17870111 · DOI 10.1016/j.juro.2007.06.046
Rats fed an oxalate precursor developed kidney crystals that partly cleared after stopping it.
Does the study support the specific claim? Unclear · Methodological quality: low
Plain-language summary
Study explained simply
- What did the researchers want to find out?
Test oxalate reduction in rats
- How was the study done?
Animal experiment
- How many people, animals or samples were studied?
Rats
- What was actually found?
Crystals formed, partly reversible
- How large was the observed effect?
Not applicable
- What do the results mean in everyday life?
No direct meaning for vegetable eating.
- What are the study's limitations?
Animal; precursor
- What does it say about Elawady's specific claim?
Very indirect
- Do the results apply to Germany and Europe?
Low
- What can explicitly not be concluded from this study?
Cannot show greens cause stones in humans.
Scientific in-depth review
1. Full reference
- Authors
- Khan SR, Glenton PA, Byer KJ
- Journal
- J Urol
- Year
- 2007
- Identifier
- PMID 17870111 DOI 10.1016/j.juro.2007.06.046
- Verification
- verified – PubMed E-utilities efetch, 2026-10-25
- Retracted
- no
- Corrections
- none
- Extent checked
- abstract only
- Conflicts of interest and funding
NIDDK NIH grant
2. Research question
Does reducing oxalate precursor intake reduce hyperoxaluria and crystal deposits?
3. Study design and population
- Study design
- Animal study – Animal experiment (rats fed hydroxy-L-proline)
- Population
Male Sprague-Dawley rats
- Country
USA
- Period
63 days
- Sample size
Not stated in abstract
- Inclusion and exclusion criteria
Rats
4. Methods and endpoints
- Exposure / intervention
5% hydroxy-L-proline (oxalate precursor) in chow
- Comparator
Discontinuation after 42 days
- Endpoints
Urinary oxalate, crystals, oxidative markers
- Statistical methods
Group comparisons
5. Actual results
- Results
Hydroxy-L-proline induced hyperoxaluria and renal CaOx deposits in all rats by day 42; after discontinuation urinary oxalate and oxidative markers fell; half of group 2 appeared crystal-free.
- Absolute risks
not reported
- Authors' conclusion
Dietary oxalate sources can induce hyperoxaluria and crystal deposition; elimination reduces them.
6. Strengths
- Controlled
7. Weaknesses
- Animal model
- Precursor, not vegetables
- n not in abstract
8. Risk of bias
- Orienting tool
- none applicable
- Type of assessment
- simplified assessment (abstract only)
- Full formal assessment
- no
- Overall risk of bias
- not assessable
- Rationale
Animal study.
9. Assessment of the statistical interpretation
Not applicable.
10. Relevance to the specific claim
Weak support for C-VEG-05.
11. Independent contrary findings
Taylor 2007; Taylor 2009.
12. Transferability to Germany and Europe
Low.
13. Overall methodological judgement
Misattributed/indirect.
| Multidimensional assessment | |
|---|---|
| Authenticity of the source | verified |
| Methodological quality | low |
| Risk of bias | not assessable |
| Precision of results | not applicable |
| Directness | very indirect |
| Reproducibility | unknown |
| Consistency with the overall evidence | unknown |
| Regional transferability | low |
| Adequacy of the interpretation (by the archive) | not supported by the study |
14. Open questions
Source of the 2.7 mg figure.
15. Linked fact checks
Use by the Tayebat archive
Note: according to the archive, the studies were compiled by the archive operators. Whether Dr. Elawady himself cited this study is not established.
- What the archive says about the study
Narrative: 'each 100 mg of dietary oxalate raises urinary oxalate by roughly 2.7 mg' (attributed to J Urol).
- A. What was actually studied?
Rats given an oxalate precursor.
- B. What did the authors find?
Hyperoxaluria and deposits, reversible.
- C. What conclusions do the authors themselves draw?
Eliminating dietary oxalate helps (in rats).
- D. What does the archive derive from it?
Used for oxalate harm of greens with a human figure.
- E. Is this derivation scientifically justified?
Not justified: the 2.7 mg figure is not in the abstract; the model does not involve vegetables or humans.
- Adequacy of the interpretation (by the archive)
- not supported by the study