Legacy AI grade · Sources dated 2026-06-08. Not expert reviewed. Coverage is limited to the listed sources. About the new summary workflow
Vitamin K for Arthritis
Verdict: Insufficient Evidence
Across 4 PubMed studies, the evidence for Vitamin K in Arthritis grades Tier U — unverified / insufficient. Research is still too limited to draw a firm conclusion.
U ⚫ U Unverified Insufficient Evidence
Why this grade7-layer evidence engine
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Scoring transparency
All scores computed by a 7-layer evidence engine — fully auditableRaw score 0.41
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C
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← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
U · Insufficient Evidence
Confidence
74%
Broadly consistent
Evidence level
E6
Multiple smaller RCTs (n<500)
▸View the full decision path (audit trail)
- compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.407
- tier_from_score — 依分數區間映射至 tier letter
- apply_hec_rules — 無高階證據可裁決
- tier_strict_requirement_check — Tier 條件達標，未降階
- detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
- decide_status — 依 tier + dispute 結果決定 status
PubMed studies (4)L2 · primary research & systematic reviews
Low vitamin K status is associated with osteoarthritis in the hand and knee (Framingham Offspring)
— See PubMed for details
View on PubMed Vitamin K in hand osteoarthritis: results from a randomised clinical trial
Finding: No significant overall effect on hand OA radiographic progression vs placebo; pre-specified subgroup of vitamin-K-insufficient participants who became replete showed less JSN progression (post-hoc, exploratory).
View on PubMed The association between vitamin K status and knee osteoarthritis features in older adults: the Health, Aging and Body Composition Study.
Finding: Plasma phylloquinone <0.5 nmol/L associated with greater prevalence of cartilage lesions (OR 1.60, 95% CI 1.07-2.39) and meniscus damage (OR 2.61, 95% CI 1.32-5.16); observational only.
View on PubMed Vitamin K2 administration is associated with decreased disease activity in patients with rheumatoid arthritis
Finding: Modest reductions in DAS28 and MMP-3 vs DMARD alone in this small open-label pilot; no blinding, no placebo, hypothesis-generating only.
View on PubMed Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …
L4a US FDA
Supportive
Vitamin K1 Injection is indicated for prophylaxis and treatment of vitamin K-deficiency bleeding in neonates source↗
L4b EU EFSA
Supportive
a cause and effect relationship has been established between the dietary intake of vitamin K and normal blood coagulation ... and the maintenance of normal bone source↗
L4c UK NHS
Cautious
You should be able to get all the vitamin K you need by eating a varied and balanced diet. Any vitamin K your body does not need immediately is stored in the liver for future use, so you do not need it in your diet every day. source↗
L4d TW TFDA / 衛福部
Supportive
成年男性 120 微克／日，女性 90 微克／日（足夠攝取量 AI） source↗
L4e WHO
Supportive
vitamin K1 should be given to all newborns as a single, intramuscular dose of 0.5–1 mg source↗
L5a NIH Office of Dietary Supplements
Supportive
Vitamin K, the generic name for a family of compounds with a common chemical structure of 2-methyl-1,4-naphthoquinone, is a fat-soluble vitamin source↗
L5e Specialty Society (condition-mapped)
Neutral
Other research suggests eating vitamin K-rich veggies like broccoli, spinach, lettuce, kale and cabbage dramatically reduces inflammatory markers in the blood. source↗