Supplement × Supplement·Evidence index
PubMed indexes 8 records that name Vitamin B12 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 Vitamin B12 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.
Strongest relevance first: papers naming both substances in the title, then human trials and systematic reviews.
“MS patients tend to have elevated Hcy blood levels compared to healthy controls. Hcy may contribute to the pathogenesis of the disease.”
Names both Vitamin B12 and Vitamin B9 in its title.
“All the patients with neurological signs and symptoms should be tested for possible vitamin B12 deficiency: early diagnosis and treatment could stop the progression of the disease and allow the regression of the neurological deficit. It is important not to rely on blood count values to diagnose a vitamin B12 deficiency as the neurological and haematological outlook may be inversely proportional.”
Names both Vitamin B12 and Vitamin B9 in its title.
“The evidence for excess folic acid exacerbating B12 deficiency is primarily correlative or from uncontrolled clinical observations, and the hypothesis to explain the phenomenon has not yet been tested. Nonetheless, the evidence is sufficiently compelling to warrant increased vigilance for identifying B12 deficiency in at risk individuals, including older adults and others with low B12 intake or conditions that are associated with B12 malabsorption, who also ingest excessive…”
Names both Vitamin B12 and Vitamin B9 in its title.
“According to the literature, vitamin B12 and folate supplementation, along with a host of novel therapies, has a considerable positive impact on MS. These findings must be kept in mind while designing newer treatment protocols in the future.”
Names both Vitamin B12 and Vitamin B9 in its title.
“Exceptions are Imerslund-Gräsbeck syndrome and hereditary folate malabsorption (affecting intestinal absorption of cobalamin and folate, respectively), transcobalamin deficiency (affecting transport of cobalamin in blood and cellular cobalamin uptake), and methylenetetrahydrofolate dehydrogenase 1 deficiency (catalyzing cytoplasmic interconversion of reduced folate coenzyme derivatives).”
Names both Vitamin B12 and Vitamin B9 in its title.
“In addition, folic acid and vitamin B12 could not only be mere cofactors in the homocysteine metabolism; they may have a direct action in determining tissue damage and cardiovascular risk. The purpose of this review was to highlight homocysteine, folic acid and vitamin B12 metabolism impairment in CKD and ESRD and to summarize available evidences on hyperhomocysteinemia, folic acid and vitamin B12 as cardiovascular risk markers, therapeutic target and risk factors for CKD…”
Names both Vitamin B12 and Vitamin B9 in its title.
“Pregnant women are exposed to folic acid at varying doses depending on the prenatal care prescribed in different countries. This review summarizes the current knowledge on the interaction between folate and vitamin B12 and the associated health outcomes.”
Names both Vitamin B12 and Vitamin B9 in its title.
“It is uncertain whether supplementation with vitamin B12 and folate can decrease fracture incidence. One double blind clinical trial in post-stroke patients showed that these B vitamins could decrease hip fracture incidence, but the results of further clinical trials should be awaited before a definite conclusion can be drawn.”
Names both Vitamin B12 and Vitamin B9 in its title.
Search-based evidence indexes have real limits, and it is worth being explicit about them:
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 Vitamin B12, 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.
