What is a Vitamin B12 Blood Test? Uses, Normal Range, Results
Vitamin B12, also known as cobalamin, is one of the B group of vitamins. An optimum level of B12 in the blood is essential for cell and tissue repair, DNA production, red blood cell formation, and nerve health. Your body can not make vit. B12 itself, it acquires it through diet. Assessing its levels in the body through a Vitamin B12 blood test is important to detect its deficiency, overdose, or ideal levels so that you can manage its healthy range accordingly.
What is a Vitamin B12 Blood Test?
A vitamin B12 blood test measures the level of cobalamin, an active form of B12, in the blood and is used to assess if the levels are enough to support vital body functions. As B12 deficiency develops gradually, tracking it regularly can help detect it earlier and take crucial steps accordingly.
At The National Blood Test Clinic, our B12 blood test is processed by an accredited UK laboratory with results delivered promptly. You can order your home kit for B12 testing too for convenience.
Symptoms of Vitamin B12 Deficiency
- Persistent fatigue and weakness
- Nausea
- Diarrhea
- Numbness or tingling in the feet and hands
- Low mood, depression, or anxiety
- Difficulty concentrating
- Memory issues
- Gradual weight loss without trying
- A sore tongue
- Trouble walking or speaking
- Who Needs Vitamin B12 Screening?
Here are a few reasons your doctor may refer you for a Vitamin B12 blood test:
- You have anaemia (red blood cell deficiency).
- You are experiencing low energy, dizziness, extreme tiredness, or memory issues.
- You feel numbness in hands and feet.
- You have a medical condition that affects your ability to absorb vitamin B12 from your gut.
- You are experiencing signs of depression or anxiety.
- You are suffering from gas.
- You are above 60 years of age.
- If you are a pregnant or breastfeeding mother.
What Does a Vitamin B12 Test Measure?
A standard B12 blood test measures the level of cobalamin (vit.B12) in the serum that reflects its concentration in the bloodstream. However, it doesn’t always give an accurate measurement of B12 status at the cellular level.
Is There Any Preparation Required for B12 Testing?
A vitamin B12 test usually requires little or no preparation. Before your test, make sure to tell your doctor about any medications, vitamins, or dietary supplements you're taking, as some supplements contain vitamin B12 and may affect the test results. Depending on the type of blood test being performed, your doctor may also ask you to avoid eating or drinking (except water) for 6-8 hours before your appointment.
Understanding the Vitamin B12 Blood Test Results (Adults)
The normal reference range used by UK laboratories is usually 180-914ng/L, though ranges vary slightly between labs.
|
Vitamin B12 Level (ng/L) |
Result |
What it May Indicate |
|
Below 145 ng/L |
Vitamin B12 Deficiency |
May be an indication of pernicious anaemia, poor dietary intake, or an overactive thyroid. |
|
Between 145 and 180 ng/L |
Borderline Range |
Your doctor may recommend additional tests, such as methylmalonic acid (MMA) or homocysteine testing, to confirm a deficiency. |
|
Above 914 ng/L |
High Vitamin B12 Levels |
May be associated with liver disease, kidney disease, diabetes, certain blood disorders (including leukaemia), or excessive vitamin B12 supplementation. Further evaluation may be required. |
Normal B12 Levels in Children
According to research, vitamin B12 levels are naturally higher in children and vary significantly by age.
- 0-1 year-olds: 215-1389 ng/L
- 2-5 year-olds: 374-1494 ng/L
- 6-9 year-olds: 332-1081 ng/L
- 10-13 year-olds: 253-871 ng/L
Is a B12 Blood Test Alone Enough?
The standard B12 level check is generally the first step and is sufficient for most clinical purposes. However, sometimes, your healthcare provider may refer to some related tests, such as homocysteine or methylmalonic acid, to get a complete picture of functional B12 availability.
Who is at Risk of Vitamin B12 Deficiency?
- People following plant-based or vegan diets
- Older adults, especially over age 60
- Patients having pernicious anaemia
- Patients taking metformin or proton pump inhibitors
Also Read: Can a Vitamin B12 Deficiency Be a Sign of Cancer?
How Much Does a Private Vitamin B12 Blood Test Cost in the UK?
At The National Blood Test Clinic, we offer private vitamin B12 testing through our network of accredited clinics across the UK, as well as convenient home blood testing kits for those who prefer to test from home. Our Vitamin B12 test prices are:
Vitamin B12 Test (Total): £173.00 GBP
Vitamin B12 Test (Active): £161.00 GBP
Conclusion
A vitamin B12 blood test is a quick and reliable way to check your vitamin B12 levels and identify deficiencies that may affect your energy, nerve function, and overall health. If you're experiencing symptoms or are at risk of deficiency, early testing can help ensure timely diagnosis and treatment.
At The National Blood Test Clinic, we offer accurate private vitamin B12 testing through accredited clinics across the UK and convenient home testing kits. Book your vitamin B12 blood test today for fast and reliable results.
