Folate and B12 (one-carbon)
Reads: One-carbon metabolism
The route from a vitamin to an epigenetic mark. Folate, B12 and B6 feed this cycle; the cycle supplies the methyl groups that DNA methylation runs on. The mthfr variants that dominate consumer genetics sit here, and their effect is on this cycle, not on methylation directly.
What this marker reads
The folate and B12 cycle that carries single carbon units for methylation and nucleotide synthesis.
What a named body publishes
Each line below is the sentence the issuing body wrote, carried with its own identifier. Nothing here interprets your result — it states what was published, for whom, and by whom.
Serum folate
“WHO defines folate deficiency on the metabolic (homocysteine) indicator as "serum or plasma folate lower than 4 ng/mL (10 nmol/L)", for all age groups.”
World Health Organization, eCatalogue of indicators for micronutrient programmes - folate status as measured by serum or plasma folate, citing WHO Vitamin and Mineral Nutrition Information System, Serum and red blood cell folate concentrations for assessing folate status in populations (WHO/NMH/NHD/EPG/15.01) · World Health Organization eCatalogue of indicators for micronutrient programmes — the entry itself carries no date; WHO/NMH/NHD/EPG/15.01 is the cited source · 2015 The document
“WHO defines folate deficiency on the haematological (macrocytic anaemia) indicator as "serum or plasma folate lower than 3 ng/mL (6.8 nmol/L)", for all age groups.”
World Health Organization, eCatalogue of indicators for micronutrient programmes - folate status as measured by serum or plasma folate, citing WHO Vitamin and Mineral Nutrition Information System, Serum and red blood cell folate concentrations for assessing folate status in populations (WHO/NMH/NHD/EPG/15.01) · World Health Organization eCatalogue of indicators for micronutrient programmes — the entry itself carries no date; WHO/NMH/NHD/EPG/15.01 is the cited source · 2015 The document
Red blood cell folate
“WHO defines red blood cell folate deficiency as "lower than 151 ng/mL (340 nmol/L)" on the homocysteine-based definition, for all age groups.”
World Health Organization, eCatalogue of indicators for micronutrient programmes - red blood cell folate, citing WHO Vitamin and Mineral Nutrition Information System, Serum and red blood cell folate concentrations for assessing folate status in populations (WHO/NMH/NHD/EPG/15.01) · World Health Organization eCatalogue of indicators for micronutrient programmes — the entry itself carries no date; WHO/NMH/NHD/EPG/15.01 is the cited source · 2015 The document
“WHO defines red blood cell folate deficiency on the macrocytic-anaemia-based definition as "lower than 100 ng/mL (226.5 nmol/L)", for all age groups.”
World Health Organization, eCatalogue of indicators for micronutrient programmes - red blood cell folate, citing WHO Vitamin and Mineral Nutrition Information System, Serum and red blood cell folate concentrations for assessing folate status in populations (WHO/NMH/NHD/EPG/15.01) · World Health Organization eCatalogue of indicators for micronutrient programmes — the entry itself carries no date; WHO/NMH/NHD/EPG/15.01 is the cited source · 2015 The document
“WHO defines red blood cell folate insufficiency in women of reproductive age as "400 ng/mL (906 nmol/L) or lower", the threshold tied to neural tube defect risk.” females, women of reproductive age
World Health Organization, eCatalogue of indicators for micronutrient programmes - red blood cell folate, citing WHO Vitamin and Mineral Nutrition Information System, Serum and red blood cell folate concentrations for assessing folate status in populations (WHO/NMH/NHD/EPG/15.01) · World Health Organization eCatalogue of indicators for micronutrient programmes — the entry itself carries no date; WHO/NMH/NHD/EPG/15.01 is the cited source · 2015 The document
Vitamin B12
“The fact sheet states that "most laboratories define subnormal serum or plasma values as those lower than 200 or 250 pg/mL (148 or 185 pmol/L)"; 148 pmol/L (200 pg/mL) is the lower of the two definitions.”
Vitamin B12 — Fact Sheet for Health Professionals · NIH Office of Dietary Supplements — updated 26 March 2024 The document
“The fact sheet's upper variant of the subnormal definition: "lower than 200 or 250 pg/mL (148 or 185 pmol/L)".”
Vitamin B12 — Fact Sheet for Health Professionals · NIH Office of Dietary Supplements — updated 26 March 2024 The document
“The fact sheet describes "low or marginal vitamin B12 status (200-300 pg/mL [148-221 pmol/L])".”
Vitamin B12 — Fact Sheet for Health Professionals · NIH Office of Dietary Supplements — updated 26 March 2024 The document
“The fact sheet describes "vitamin B12 insufficiency (assessed as serum vitamin B12 <300 pg/mL [221 pmol/L])".”
Vitamin B12 — Fact Sheet for Health Professionals · NIH Office of Dietary Supplements — updated 26 March 2024 The document
Methylmalonic acid
“The fact sheet states "an MMA level greater than 0.271 micromol/L suggests vitamin B12 deficiency" (methylmalonic acid, a functional B12 marker).”
Vitamin B12 — Fact Sheet for Health Professionals · NIH Office of Dietary Supplements — updated 26 March 2024 The document
Homocysteine
“The fact sheet states "a serum homocysteine level higher than 15 micromol/L, for example, suggests vitamin B12 deficiency".”
Vitamin B12 — Fact Sheet for Health Professionals · NIH Office of Dietary Supplements — updated 26 March 2024 The document
Your laboratory reads your result against its own assay, and this page does not do that for it. What is above is what a named body published and for whom; what is below is the machinery the marker reads and the formulas witnessed on it.
What moves it
Micronutrient status raises it.
Folate, B12 and B6 are the cofactors this cycle runs on. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
Glycine calming raises it.
The serine-glycine interconversion is a principal one-carbon source. Carried by the intermediary-metabolism, micronutrient and redox reviews. doi 10.3390/nu18132141 · PMC9967593
Riboflavin cofactor raises it.
MTHFR is A FLAVOPROTEIN - riboflavin status modifies the effect of the MTHFR variants people test for, and the variant most discussed is the one that destabilizes the FAD cofactor. Carried by the intermediary-metabolism, micronutrient and redox reviews. doi 10.3390/nu18132141 · PMC9967593
What it moves
It raises Universal methyl donor.
The cycle regenerates methionine, from which SAMe is made. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
It lowers Homocysteine.
Remethylation consumes homocysteine and returns it to methionine. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
It raises Iron & oxygen carriage.
Folate and B12 deficiency produce megaloblastic anemia through impaired nucleotide synthesis. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
It raises Female fertility.
Folate status is the best-established periconceptional nutritional factor. Carried by the intermediary-metabolism and clinical reviews. doi 10.1016/j.molmet.2023.101755 · PMC9967593
Formulas that modulate it
Each formula page names this pathway and carries the study behind its claim.
Build a combo from your panel
Open the bloodwork builder and select every marker your lab flagged — it covers the most machinery with the fewest formulas.