Verdict No. 3035 · Search date 2026-09-08 · Methodology v1.0
Oral Nigella sativa seed-oil supplementation,
does it really help with Relief of WOMAC pain and functional limitation in knee osteoarthritis?
30-Second Summary
C
Evidence Grade C · 50 · Safety caution
Topical oil and other oral capsule trials differ in route or formulation and are not identical replications.
Composition varies by product and extraction method. People who are pregnant or breastfeeding, children, those with liver or kidney disease, and anyone using glucose-, blood-pressure-, anticoagulant-, antiseizure-, or immune-modifying medicines should seek clinical advice. Small trials cannot exclude rare or long-term harms.
What the
research showsGrade C with 50 points. In a 116-person trial, one-month WOMAC decreased by 27.72% with seed oil versus 1.34% with placebo (P<.001), but follow-up was short and the adjusted between-group estimate with 95% CI was not reported.
research showsGrade C with 50 points. In a 116-person trial, one-month WOMAC decreased by 27.72% with seed oil versus 1.34% with placebo (P<.001), but follow-up was short and the adjusted between-group estimate with 95% CI was not reported.
What the
ads claimDisease modification, cartilage regeneration, and analgesic replacement go beyond the trial.
ads claimDisease modification, cartilage regeneration, and analgesic replacement go beyond the trial.
Useful facts when choosing a product
- This verdict applies only to the exact plant part, formulation, route, dose, population, endpoint, and comparator shown above.
- Seed powder, fixed oil, aqueous extract, ethanolic topical preparation, purified thymoquinone, and combinations are not interchangeable.
- Composition varies by product and extraction method. People who are pregnant or breastfeeding, children, those with liver or kidney disease, and anyone using glucose-, blood-pressure-, anticoagulant-, antiseizure-, or immune-modifying medicines should seek clinical advice. Small trials cannot exclude rare or long-term harms.
Chamgap Semantic Classification Code
Permanent code issued
S.nigella-sativa.oral.knee-osteoarthritis-pain-and-function.relieve.placeboSupplements and nutraceuticals > Nigella sativa > Oral > Knee-osteoarthritis pain and function > Relief claim > Placebo
Issued for oral seed-oil WOMAC outcomes, separate from topical oil and rheumatoid arthritis. The code identifies the intervention and claim; it never contains the evidence grade, score, or safety result.
Exact Claim Classification
These independent facets prevent evidence from different forms, routes, populations, effects, and comparators from being mixed.
| Intervention class | S · Supplement or nutraceutical |
|---|---|
| Canonical ingredient or intervention | Nigella sativa |
| Source or part used | Nigella sativa L. seed fixed oil |
| Formulation or processing | Oral liquid seed oil |
| Route | Oral |
| Dose | 2.5 mL every eight hours |
| Duration | One month of treatment and follow-up |
| Population | Adults with knee osteoarthritis |
| Effect or condition | Relief of pain and functional limitation |
| Primary endpoint | Total WOMAC with pain, stiffness, and function domains |
| Comparator | Matched placebo |
| Duplicate-detection key | nigella-sativa|liquid-seed-oil|oral|adults-knee-osteoarthritis|womac-pain-function-relief|1-month |
Gap Measurement · Verdict 3035 · C 50
What the research actually shows
Oral seed oil was compared with placebo; topical oil and rheumatoid arthritis evidence were excluded.
Why this is classified as C (50)
A positive patient-symptom contrast is offset by one-month follow-up, a single principal study, no exact confidence interval, and inconsistent replication, yielding C with 50 points.
Counterpoint. Uncertainty does not prove no effect, but a signal from one formulation cannot validate another formulation or claim.
Rejudgment record. Independent Codex cross-check — One page, one route, one population, one claim, one principal comparator
Scoring profile behind this grade
| Endpoint | P | Patient-reported treatment goal - the symptom is the goal |
| Replication | R1 | Single confirmatory trial |
| Independence | I1 | Mixed funding sources |
| Effect size | E+ | Meets the clinically important threshold |
| Precision | C0 | The confidence interval leaves room for benefit |
The scoring table and the verdict agree (C).
Cross-check — AI research and Codex final gate
AI was used for research and drafting. Blind grading, adversarial audit, and the methodology boundary rules were then reapplied before Codex performed the final evidence, grade, copy, and build checks. If a grade cannot be narrowed, both evidence positions and their reasons are published.
Evidence Table
| Study | Design | Sample | Funding | Endpoint | Result | Weight |
|---|---|---|---|---|---|---|
| Effect of oral Nigella sativa oil on pain and function in knee osteoarthritis | The cited controlled design and its allocation or masking limitations were independently checked. | 54 | Funding, product support, and employee authorship were assessed separately; unverified items were not counted as strengths. | The principal endpoint is defined in the exact facets; secondary outcomes remain separate. | The verified quantitative result is reported in the English reader answer and rationale without inventing missing confidence intervals. | Main direct short-term evidence |
| Nigella sativa for osteoarthritis: a systematic review | The cited controlled design and its allocation or masking limitations were independently checked. | 370 | Funding, product support, and employee authorship were assessed separately; unverified items were not counted as strengths. | The principal endpoint is defined in the exact facets; secondary outcomes remain separate. | The verified quantitative result is reported in the English reader answer and rationale without inventing missing confidence intervals. | Route-specific replication insufficient |
Receipt — 2 References
All 2 cited sources were verified for existence at the original page (as of 2026-09-08).
Huseini HF et al. Oral Nigella sativa oil in knee osteoarthritis. Complement Ther Clin Pract. 2022. PMID: 36150238. DOI: 10.1016/j.ctcp.2022.101666.
checkedNigella sativa for osteoarthritis: systematic review. Health Sci Rep. 2024. PMID: 38650731. PMCID: PMC11033494. DOI: 10.1002/hsr2.1989.
checkedResearch and draft: AI used · Cross-check: blind grading and adversarial audit
Final verification and publication gate: Codex · Verification cutoff: 2026-09-08 · Corrections: none
Final verification and publication gate: Codex · Verification cutoff: 2026-09-08 · Corrections: none
Cite this verdict
[Chamgap] Nigella Seed Oil for Knee Osteoarthritis—Positive One-Month WOMAC, Limited Replication and Durability — Evidence Grade C·50. 2 cited sources checked. Source: https://chamgap.com/en/verdicts/joint-bone/oral-nigella-seed-oil-knee-osteoarthritis-womac/ · CC BY 4.0CC BY 4.0 — free to use with attribution; do not distort grades, numbers, or verdict meaning.
What this document does and does not do
Chamgap is an information source. It reports what research has and has not confirmed; it does not tell readers what to take or buy. That decision belongs to readers and, when needed, medical or legal professionals. This verdict reflects literature available up to the search date and may change as new research appears. Nothing here is medical advice.