Vitamin B12 and folate
vitamin B12 test · folate test · folic acid level · B12 deficiency test
This is a blood test from a vein. It shows whether your body has enough vitamin B12 and folate.
For anemia, weakness, numb hands and feet, a vegetarian diet, when planning a pregnancy, or while taking certain medicines.
⏱ Duration: the blood draw takes a few minutes; results usually come in 1 to 3 days
Be sure to tell your doctor
How to prepare
- Food. Usually fasting: no food for 8 to 12 hours. Plain water is fine. Check with the lab.
- The day before. For 24 hours, no alcohol and no hard workouts. Best not to smoke in the morning.
- Vitamins. Do not stop them on your own. Tell your doctor which vitamins you take. They will decide if you need a break before the test.
What to bring
- Your test request form
- Your ID
How it goes
- You sit down and rest your arm on the armrest
- A band is tightened above your elbow
- The skin is wiped with antiseptic
- A quick prick, and blood fills a tube
- The needle comes out, and a cotton pad is pressed on the spot
What you'll feel
- A quick prick, like a pinch
- Sometimes slight dizziness. Tell the nurse
Afterwards
- Press the cotton pad for 3 to 5 minutes and keep your arm straight
- You can eat right away and go back to your usual day
- Results usually come in 1 to 3 days. The lab will tell you when
Common questions
Should I stop vitamins before the test?
Do not stop on your own. Tell your doctor. They will decide if a break is needed and how long.
Why can B12 be low if I eat meat?
Sometimes the body does not absorb it well. Your doctor will find the cause.