What is Folate?
Folate (vitamin B9) is essential for DNA synthesis, cell division, and red blood cell formation. The synthetic form, folic acid, is used in supplements and fortified foods. Adequate folate before and during early pregnancy prevents neural tube defects. Deficiency causes a type of anemia similar to B12 deficiency.
Why it matters
Folate is vital for rapidly dividing cells, making it especially important in pregnancy. Deficiency causes megaloblastic anemia and raises homocysteine, and low folate around conception increases birth defect risk.
What it measures
Serum or red blood cell folate. RBC folate reflects longer-term status; serum folate reflects recent intake.
Reference & optimal ranges
Reference ranges vary by lab, assay, age, and sex. The ranges below reflect commonly published adult intervals and are for education only always interpret results with the range printed on your own lab report and a clinician.
High folate is generally harmless but can mask a co-existing B12 deficiency, allowing nerve damage to progress.
Common symptoms
- Usually none
Potential causes
- Supplementation or fortified foods
- Recent high dietary intake
Low folate causes megaloblastic anemia and, around conception, raises the risk of neural tube defects.
Common symptoms
- Fatigue and weakness
- Mouth sores, sore tongue
- Irritability
- Pale skin
- Shortness of breath
Potential causes
- Inadequate intake (few vegetables)
- Pregnancy (increased needs)
- Alcohol use
- Malabsorption
- Certain medications (methotrexate)
How to improve your Folate
Lifestyle
Supplement before pregnancy
People who could become pregnant should get 400 mcg folic acid daily to prevent neural tube defects.
Nutrition
Folate-rich foods
Leafy greens, legumes, citrus, and fortified grains are excellent sources.
Exercise
General activity
No direct link; supports overall health.
Sleep
General health
Fatigue improves once deficiency is corrected.
Frequently asked questions
Scientific references
- Folate Fact Sheet for Health Professionals NIH Office of Dietary Supplements (2022)
- Folate Test MedlinePlus, U.S. National Library of Medicine
Educational information, not medical advice. This page is for general education and does not replace diagnosis or treatment by a licensed clinician. Do not start, stop, or change any medication, supplement, or treatment based on this content. Reference and optimal ranges vary between laboratories interpret your results with the range on your own report and a qualified professional.