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Supplements

L-methylfolate treats mood disorder

Leans against Supplements 🔬 Includes disconfirming

Part of: 🧪 Folate & L-methylfolate

RefutedContestedStrong support
consensus score -0.32

📅 Last reviewed: 2026-07-15

Evidence ladder

How far up the ladder this claim has climbed. A high consensus on a low rung means "consistent so far," not "proven in people."

Top evidence so far: All trials, pooled (Meta-analysis)

MechanismIn-vitroAnimalObservationalRCTMeta-analysis

How the studies fall

2 support 2 contradict 0 tested null 3 mixed · 7 sources, 4 independent groups

What the evidence shows

L-methylfolate (15 mg/d) augments antidepressant response in SSRI-resistant depression.

The evidence (7)

SourceGradeStanceQualityFinding
Bopp EA et al
2022 · study_type: observational
observational contradicts moderate Retrospective EHR, n=412 youth: CGI-I change did not differ by L-methylfolate prescription (p=0.39); response not assoc. w/ Rx (p=0.17) or dose (p=0.69), regardless of MTHFR C677T genotype
Siddique A et al
2025 · study_type: RCT
observational mixed low Open-label, n=44, methylfolate 800µg add-on: 40.33% vs 26.43% symptom improvement (p<0.05) at d28; remission rate NOT significant; day-14 time-lag NOT significant
papakostas-2012
2012
RCT supports moderate L-methylfolate 15 mg augmented SSRI response in resistant MDD (2 RCTs).
Liwinski T et al
2023 · study_type: observational
observational supports low Narrative review: 'findings have been mixed' but concludes evidence 'generally supports' folic acid/L-methylfolate as adjunct/stand-alone in depression
Macaluso M
2022 · Front Psychiatry
observational mixed low DESIGN NOTE: a single-author narrative summary ('this summary provides context'), NOT a trial - graded observational/low per CONVENTIONS narrative-review rule. Argues LMF benefit concentrates in antidepressant non-responders with elevated BMI/inflammation; that stratified rationale remains post-hoc and hypothesis-level. L-methylfolate is a commercial product, so weigh authorship interest.
Cheng 2025
2025 · Psychol Med
meta-analysis mixed moderate network MA: methylfolate efficacy ranking modest/uncertain
Roberts 2018
2018 · J Psychopharmacol
meta-analysis contradicts high SR/MA: folate-derivative evidence in depression weak/contradictory

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Educational only, not medical advice. Grades and scores reflect published evidence weighted by study design and quality; see the methodology.