Vitamin B12 for Masld

Verdict: Counter-Evidence

Across 6 PubMed studies, the evidence for Vitamin B12 in Masld grades Tier D — counter-evidence. High-quality evidence indicates it is not effective (or is harmful) for this use.

D 🔴 D Counter-Evidence Counter-Evidence

🔬Why this grade7-layer evidence engine

⚖️

Scoring transparency

All scores computed by a 7-layer evidence engine — fully auditable
Raw score 0.47
D
C
B
A
S
← counter-evidence / ineffectiveeffective / strong evidence →
Final grade
D · Counter-Evidence
Confidence
90%
Highly consistent evidence
Evidence level
E3
Single high-quality meta-analysis

How strongly each layer supports this effect

lower = less supportive
L11 AI re-checkIndependent read
0.30
L2 PubMedPrimary literature
0.45
L3 MechanismPlausibility
0.45
L1 ExamineGlobal benchmark
0.50
L5 Clinical bodiesAuthoritative stance
0.55
Against Mixed Supports
View the full decision path (audit trail)
  1. compute_raw_score — 加權公式: L2×0.30 + L3×0.25 + L5×0.25 + L11×0.10 + L1×0.10 = 0.465
  2. tier_from_score — 依分數區間映射至 tier letter
  3. apply_hec_rules — 無高階證據可裁決
  4. tier_strict_requirement_check — Tier 條件達標,未降階
  5. detect_disputes — 偵測到 0 個 hard + 0 個 soft dispute
  6. decide_status — 依 tier + dispute 結果決定 status

📄PubMed studies (6)L2 · primary research & systematic reviews

Bi-directional causal effect between vitamin B12 and non-alcoholic fatty liver disease: Inferring from large population data
PMID: 36950332 2023 Cohort n = 45,576
Finding: Genetically predicted higher vitamin B12 was associated with INCREASED NAFLD risk (combined OR 1.30, 95% CI 1.13-1.48, p<0.001 per SD), with reverse causality also seen (NAFLD liability raised B12, beta 0.08, p=0.034).
Effect size: OR 1.30 (95% CI 1.13-1.48) per SD increase in B12
View on PubMed
The effects of vitamin B12 supplementation on metabolic profile of patients with non-alcoholic fatty liver disease: a randomized controlled trial
PMID: 35982162 2022 RCT (double-blind) n = 40
Finding: B12 significantly lowered the surrogate marker homocysteine vs placebo (median -2.1 vs -0.003 umol/L, p=0.038), but between-group differences in liver steatosis, ALT and fasting glucose were NOT significant.
🟠 Limited quality Academic Effect size: Homocysteine change -2.1 vs -0.003 umol/L (p=0.038); no significant between-group change in steatosis/ALT
View on PubMed
Use of a Micronutrient Cocktail to Improve Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) in Adults with Obesity: A Randomized, Double-Blinded Pilot Clinical Trial
PMID: 39202647 2024 RCT (double-blind) n = 196
Finding: The B12-containing cocktail reduced CAP by 4% and TE by 7.8% vs placebo (both p<0.05), but B12 was co-administered with folate, betaine, omega-3 and choline so its independent effect cannot be isolated.
🟠 Limited quality Government Effect size: CAP -4% (p<0.05); TE -7.8% (p<0.05) for combined cocktail
View on PubMed
Associations of serum folate and vitamin B12 levels with all-cause mortality among patients with metabolic dysfunction associated steatotic liver disease: a prospective cohort study
PMID: 39703860 2024 Cohort n = 2,125
Finding: Higher serum B12 was associated with LOWER all-cause mortality (Q3 HR 0.58, 95% CI 0.39-0.86, p=0.008; Q4 HR 0.72, 95% CI 0.54-0.96, p=0.026), but this is observational and likely confounded by reverse causation (low B12 marking sicker patients).
Effect size: Q3 HR 0.58 (0.39-0.86); Q4 HR 0.72 (0.54-0.96) vs lowest quartile
View on PubMed
The Association between Non-Alcoholic Fatty Liver Disease (NAFLD) and Advanced Fibrosis with Serological Vitamin B12 Markers: Results from the NHANES 1999-2004
PMID: 35334881 2022 Cross-sectional n = 8,397
Finding: Functional B12-pathway markers were associated with advanced fibrosis (homocysteine OR 2.76, 95% CI 1.49-5.11; methylmalonic acid OR 1.41, 95% CI 1.10-1.80), indicating impaired B12 metabolism tracks with worse disease rather than B12 being protective.
Government Effect size: Homocysteine OR 2.76 (1.49-5.11); MMA OR 1.41 (1.10-1.80) for advanced fibrosis
View on PubMed
The Role of Vitamins in Non-Alcoholic Fatty Liver Disease: A Systematic Review
PMID: 34522493 2021 系統性回顧 n = 17
Finding: Narrative review of 17 studies concluded vitamin deficiency associates with NAFLD and that B12 shows 'promise', but found no quantitative pooled effect and explicitly stated more well-designed human trials are needed.
🟠 Limited quality
View on PubMed

🏛️Regulatory & authoritative positionsL4/L5 · FDA / EMA / NIH ODS / Cochrane / Mayo …

L4a US FDA
Supportive
NUTRIENT SUPPLEMENT source↗
L4b EU EFSA
Supportive
a cause and effect relationship has been established source↗
L4c UK NHS
Supportive
Adults aged 19 to 64 need about 1.5 micrograms a day of vitamin B12. source↗
L4d TW TFDA / 衛福部
Supportive
維生素B12之足夠攝取量(AI)成人為每日2.4微克 source↗
L4e WHO
Supportive
Vitamin B12 or folate supplementation during pregnancy is not recommended as an intervention to improve maternal and infant health outcomes source↗
L5a NIH Office of Dietary Supplements
Supportive
Vitamin B12 supplementation appears to have no beneficial effect on performance in the absence of a nutritional deficit. source↗
PMID 100% verifiedevery citation checked via NCBI Entrez
🔬6 PubMed studiesindependently re-checked by multiple sub-agents
engine_version: v1.0 claim_id: CLM-COND-masld-INT-vitamin-b12-001 繁體中文版 →