What it does
Supports DNA synthesis and one-carbon metabolism, including the pathway that processes homocysteine.
Possible deficiency symptoms
Deficiency may cause megaloblastic anemia, fatigue and mouth changes. A homocysteine result alone cannot identify folate deficiency.
Food sources
Leafy greens; lentils; chickpeas; asparagus; citrus; fortified grains.
Supplement forms
Folic acid, folinic acid and 5-MTHF (methylfolate) are different forms. A common MTHFR variant alone does not establish a need for a particular supplement.
Before taking a supplement
Check B12 context before taking high amounts. Pregnancy planning has specific folic-acid guidance; discuss it with your clinician.
Questions for your visit
Could my diet, medicines, absorption or another condition explain my concern? What evidence would support treatment, and how would we check whether it helps?
Names you may see
Vitamin B9 (Folate) · Folate · B9 · folic acid · methylfolate · 5-MTHF · folinic acid · foods high in folate
Sources & perspective
This is an editorial adaptation of the Purser Wellness nutrient reference app. Purser teaching connections are labeled separately from clinical interpretation. Private cases and individual treatment protocols are not reproduced.
Use the public resources below for additional context.
NIH Office of Dietary Supplements: Vitamin B9 (Folate)
