Methylcobalamin and Vitamin B9: what the published research says
PubMed indexes 8 records that name Methylcobalamin and Vitamin B9 together, either in the title or in an interaction, co-administration, or pharmacokinetic context. Each one is listed below with its study design and, where the abstract states one, the authors’ own conclusion, quoted and linked. This page reports that literature. It does not tell you whether to combine them.
Every statement below is attributed to a named, dated, linked source.
This page lists published research relevant to Methylcobalamin and Vitamin B9. It deliberately does not state whether the combination is safe, whether it interacts, in which direction, at what dose, or how far apart to take them.
A study appearing here is not proof that an interaction exists. Two substances can be named together in a paper that never tested them in combination, and a source listed as background may cover only one of them.
Findings are quoted from each abstract as the authors wrote them. NutriStack has not re-analysed, pooled, or reconciled them, and they may disagree with each other.
NutriStack’s own interaction assessment for this pair is not published here. It has not completed qualified-human clinical review, so it is withheld from search. See the publication gate.
Nothing here is medical advice. Decisions about prescription medication and supplements belong with your prescriber or pharmacist, who can see your full regimen.
The research
8 studies naming Methylcobalamin and Vitamin B9.
Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.
“A three-month supplementation with a combination of 800 mcg methylfolate and 1000 mcg methylcobalamin showed promise in lowering blood pressure and serum homocysteine levels in ESRD patients with resistant hypertension. These findings require additional exploration in larger studies.”
Names both Methylcobalamin and Vitamin B9 in its title.
“LDL-C levels decreased by 11.8% in homozygous carriers (95% CI: -15.8% to -7.8%, p < 0.01) and 4.8% in mixed allele carriers (95% CI: -6.8% to -2.8%, p < 0.01), with a significant between-group difference (7.0%, 95% CI: -13.0% to -1.0%, p < 0.01). Methylfolate, P5P, and methylcobalamin supplementation tailored to genetic profiles effectively reduced homocysteine and LDL-C levels in patients with specific MTHFR, MTR, and MTRR polymorphisms, particularly with homozygous minor…”
Names both Methylcobalamin and Vitamin B9 in its title.
American journal of kidney diseases : the official journal of the National Kidney Foundation · 2010 · PMID 20430500
Randomized Controlled Trial20 participants
“Coadministration of intravenous methylcobalamin and oral folate in hemodialysis patients normalized hyperhomocysteinemia and decreased ADMA levels and arterial stiffness. We suggest that this regimen may have greater potential than folate alone to decrease cardiovascular risk in such patients.”
Names both Methylcobalamin and Vitamin B9 in its title.
“Oral FA (10 mg/day) supplementation appears to be an effective approach to normalize plasma tHcy in chronic HD patients; the addition of i.v. Me-Cbl (500 microg twice/week) to this regimen showed no benefit. Separately, FA corrected hyperhomocysteinemia (HtHcy), while Me-Cbl showed no change.”
Names both Methylcobalamin and Vitamin B9 in its title.
“However, vitamin B12 and folate levels may not strongly influence MCI. Routine assays for these vitamins in elderly individuals with cognitive impairment should be reconsidered in resource-constrained settings.”
Names both Methylcobalamin and Vitamin B9 in its title.
“Their pregnancy outcomes improved with L-methylfolate and methylcobalamin supplementation. L-methylfolate and methylcobalamin supplementation merits further study in WWE who have MTHFR mutations, fertility, recurrent miscarriage and or depression histories.”
Names both Methylcobalamin and Vitamin B9 in its title.
“These results suggest that prenatal iAs exposure impairs glucose metabolism in a sex-specific manner and that maternal folate/B12 supplementation may improve the metabolic phenotype in offspring. Further studies are needed to identify the mechanisms underlying these effects.”
Names both Methylcobalamin and Vitamin B9 in its title.
Limitations
What this evidence cannot tell you.
Search-based evidence indexes have real limits, and it is worth being explicit about them:
Selection. These records were found by searching PubMed titles and abstracts for both substance names alongside interaction and pharmacokinetic terms. Relevant work that phrases things differently, or is not indexed in PubMed, will be missing.
No effect size. The quoted conclusions are the authors’ words about their own study. We have not extracted effect direction or magnitude, and a single study’s conclusion is not a consensus.
Population mismatch. Findings in healthy volunteers, animals, or a specific patient group may not transfer to you, your dose, or your formulation.
Absence is not safety. Few published studies means the combination is under-studied, which is not the same as established as safe.
Nearby evidence
Other pairs with published research.
Pages covering Methylcobalamin or Vitamin B9 alongside a different substance.
NutriStack is a free iPhone app for organising a supplement routine: what you take, when, and what the published record says about it. Its exploratory interaction checker covers Methylcobalamin, Vitamin B9, and several hundred other substances.
The checker is a research and organisation tool, not a clinical decision aid, and its per-pair assessments are excluded from search until they pass claim-level review.
NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.
