Folate (serum)

Routine annual

also vitamin b9

What it isFolate is a B vitamin essential for DNA synthesis, red blood cell production, and the methylation cycle. Serum folate reflects recent intake.

DoesProvides single-carbon units used in DNA synthesis, amino acid metabolism, and the conversion of homocysteine back to methionine.

GoodHigh-normal folate supports methylation, red cell production, and cardiovascular health through homocysteine control.

BadLow folate causes megaloblastic anemia, elevated homocysteine, and in pregnancy, neural tube defects. Excess synthetic folic acid can mask B12 deficiency.

Standard

>5.4 ng/mL.

Optimal

12–24 ng/mL (higher is good)

Modifiers

Falls with alcohol, methotrexate, anticonvulsants; MTHFR variants affect activation.

How to optimize

Lifestyle: Cut alcohol.
Diet: Leafy greens, legumes, asparagus, beets, citrus, eggs.
Supplements: Methylfolate (400–800µg/day) — the active form, preferred over folic acid especially in MTHFR variants.
Peptides: —
Drugs: —

within Vitamins