Serum Folate and Vitamin B12 Levels with Combined Interpretation
This test measures your blood levels of folate (a B vitamin) and vitamin B12 (another essential B vitamin) to check if your body has enough of these nutrients.
["Your body needs these vitamins to stay healthy, especially for red blood cell production and nerve function."]
Key facts at a glance
- LOINC
- 14733-0
- Short code
- Folate+Vit B12 SerBld-Imp
- Synonyms
- Folate+Vit B12 SerBld-Imp
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 200
- Ref high
- 900
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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 doctor may recommend this test if you have symptoms like fatigue, weakness, numbness, or unusual bruising. It’s also used to diagnose or monitor conditions like anemia, nerve problems, or deficiencies in these vitamins.
What to Expect Before the Test
No special preparation is needed, but you may need to fast for 8–12 hours before the test if your blood is drawn early in the morning. Bring any medications you’re taking to your appointment.
What the Test Involves
A healthcare provider will draw blood from a vein in your arm. The blood will be sent to a lab for testing. The results will include separate measurements for folate and vitamin B12, along with an interpretation of whether your levels are within a healthy range or if further action is needed.
What the Results Mean
Low levels of either folate or vitamin B12 can indicate deficiencies, which may require dietary changes, supplements, or medical treatment. Your doctor will discuss the results with you and explain next steps based on your specific situation.
Reference range
NCBI: Vitamin B12 200-900 pg/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.
Low folate or vitamin B12 levels can cause anemia (reduced red blood cells), nerve damage, or other health issues. These vitamins are crucial for DNA synthesis, red blood cell production, and maintaining nerve function. Your doctor may recommend adjustments to your diet, supplements, or further testing if deficiencies are found.
Short name
Folate & B12 Profile
Frequently asked questions
How long does it take to get my results?
Can I eat or drink anything before the test?
What should I do if I have symptoms of deficiency?
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