Serum Folate (Folic Acid) Measurement
This test measures the amount of folate (also called folic acid) in your blood. Folate is a type of B vitamin that helps your body make healthy red blood cells and DNA.
["Folate helps prevent certain birth defects and supports overall red blood cell health."]
Key facts at a glance
- LOINC
- 61517-9
- Short code
- Folic acid folate PhenX
- Synonyms
- Folic acid folate PhenX
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 2.7
- Ref high
- 17
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- phenx
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Might Be Ordered
Your healthcare provider may recommend this test if you have symptoms like fatigue, weakness, or pale skin, which could indicate low red blood cell counts. They might also order it if you have a history of alcohol use, poor diet, or certain medical conditions that affect folate absorption. Pregnant women may also be tested to ensure proper folate levels for fetal development.
What to Expect Before the Test
No special preparation is usually needed. You may be asked to fast for 8–12 hours before the test if your blood is drawn early in the morning. Bring any medications you’re taking, as some may affect results.
How the Test Is Performed
A healthcare professional will draw blood from a vein in your arm using a small needle. The blood sample is then sent to a lab for analysis using an immunoassay method to measure folate concentration.
What the Results Mean
Results are reported in micrograms per deciliter (mcg/dL). Low levels may indicate deficiencies from poor diet, malabsorption, or certain medications. High levels could suggest folate supplements or liver disease.
Reference range
NCBI: Folate 2.7-17.0 ng/mLN/A
Fasting for 8-12 hours preferred for some tests. Inform about supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Folate Level
Frequently asked questions
Low folate levels can lead to anemia, neurological issues, or increased risk of birth defects in pregnancy. High levels may mask vitamin B12 deficiency, which can cause serious nerve damage. Regular monitoring helps manage conditions like alcoholism or gastrointestinal disorders.
A low folate level may mean you’re not getting enough folate from your diet, have an absorption issue, or are taking certain medications that deplete it. Your provider may suggest dietary changes, supplements, or further testing to identify the cause.
Yes, diet plays a major role. Foods like leafy greens, beans, fortified cereals, and liver are rich in folate. Even small dietary adjustments can impact results, so consistency matters.
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 17, 2026. · Read our editorial policy