Folate (Serum)
What This Test Measures
B-vitamin for DNA synthesis, methylation, red blood cells
Conventional vs. Functional Optimal Range
The gap between these ranges is why you feel terrible with "normal" labs. Conventional medicine waits for disease. Functional medicine optimizes for health.
Gabriel's Take
Gabriel's optimal band for serum folate is 15-27 ng/mL; many labs print ">20" or ">24", which meets it. Serum folate reflects the last few days of intake, so read it with B12 and homocysteine. Low folate + high homocysteine = cardiovascular and cognitive risk. Folic acid and methylfolate both raise folate. The CDC says people with MTHFR variants can process folic acid, and it is the form proven to lower neural tube defect risk, so it stays the recommendation for anyone who could become pregnant, including in prenatal vitamins. Methylfolate is an option, not a requirement. High folic acid intake can hide a B12 deficiency. Full guide: askgabriel.com/guides/folic-acid-vs-methylfolate.
When This Test Is High
High supplementation
When This Test Is Low
Deficiency: anemia, birth defects, elevated homocysteine
Related Conditions
Anemia, neural tube defects, cardiovascular disease
Recommended Follow-Up
If low, check B12 and homocysteine and raise folate with food and a supplement your clinician suggests: folic acid and methylfolate both work. If you could become pregnant, take 400 mcg of folic acid daily (CDC)