What is folate and how is it different from folic acid?
Folate is vitamin B9; folic acid is the synthetic form. Both repair DNA and support methylation. Most US deficiency cases involve alcohol use, methotrexate, or malabsorption rather than diet.
Full answer
Folate (vitamin B9) is essential for DNA synthesis, methylation, and red blood cell formation. It works in tandem with B12; deficiency in either produces macrocytic anemia. Outside pregnancy, isolated folate deficiency is uncommon in the US due to food fortification but remains relevant in alcohol use, methotrexate therapy, and malabsorption disorders. Folic acid is the synthetic form added to fortified foods and supplements; methylfolate may be preferred in MTHFR variants. The critical clinical caveat: high folate intake can mask the macrocytosis of B12 deficiency while neurologic damage progresses. Always assess both.
Educational. Not a substitute for individualized provider review.
- Folate — Primary source · oMeds
- Reviewed by Dr. Laura Purdy, MD, MBA · Clinical Director, oMeds · Last reviewed 2026-05-29