B12 Blood Test
£99
Excellent 4.9 Rating
20% off with code BFBL20
Biomarkers Included with the B12 Blood Test blood test
Scroll down for more information about each biomarker
Vitamin B12
Why choose us for your B12 Blood Test
About the B12 Blood Test blood test
The B12 blood test (also known as a serum cobalamin test) measures the amount of vitamin B12 circulating in your bloodstream.
Vitamin B12 plays vital roles in:
- Making new red blood cells.
- Maintaining the nervous system (nerve health)
- DNA synthesis and tissue repair.
While your body cannot manufacture vitamin B12, it obtains it via diet (mainly animal‐derived foods) and absorbs it through the stomach and small intestine.
About The Vitamin B12 blood test
The vitamin b12 blood test is a valuable screening tool for assessing your vitamin B12 status, which influences blood production, nerve function and general health. If you are experiencing symptoms consistent with B12 deficiency or are in a higher-risk group, a simple blood test can provide clarity and help your doctor with next steps. At The Scan Clinic we provide a simple, high-quality service with fast results and clear reporting.
Why is the B12 Blood Test Performed?
Your clinician may recommend a b12 blood test if you’re experiencing symptoms or belong to a higher‐risk group. Some common reasons include:
- Feeling unusually tired, weak, or short of breath (possible anaemia)
- Numbness, tingling or “pins and needles” in hands or feet
- Changes in mood or memory, or balance problems in older age
- A diet low in B12 (for example a strict vegan diet)
- Conditions or medications that impair absorption of vitamin B12 (e.g., gastrointestinal surgery, pernicious anaemia, long‐term use of acid-reducing drugs)
- Routine screening if your healthcare professional suspects a deficiency or wants to confirm your nutritional status
What Do the Results Mean?
Because reference ranges vary between laboratories, your results should always be discussed with a qualified professional. Broadly speaking:
- A result below the lower threshold may suggest a B12 deficiency (or borderline deficiency) and the need for further investigation Office of Dietary Supplements
- A result within the “normal” range is reassuring but doesn’t entirely rule out functional deficiency (i.e., where B12 levels appear adequate but the body still can’t use it properly). NHS Inform
- A result above the normal range is less common and may warrant investigation of underlying causes (for example liver disease or other conditions) rather than simply “excess B12”.
Important note: Your result forms only part of the picture—symptoms, clinical signs and other tests (e.g., methylmalonic acid, homocysteine) may be needed for a full assessment.
How is the Test Performed?
The b12 blood test is straightforward and similar to a standard venous blood draw.
- A small tourniquet is placed, a suitable vein (typically in the arm) is located.
- A needle is inserted and a small amount of blood collected into a tube.
- A plaster is applied over the puncture site; you can resume normal activity immediately afterwards.
How to Prepare
To ensure the most reliable result:
- It’s advisable to wear clothing with easy access to your arm.
- If you take a B12 supplement, your clinician may ask you to avoid it for a short period prior to testing (day-of instructions will be given).
- If the B12 test is part of a broader blood panel, you may be asked to fast (typically 6–8 hours) – please follow the booking instructions.
Important notes:
The B12 blood test is not a diagnostic test for any specific disease—it assesses vitamin B12 status only. Results should always be interpreted in the context of your full medical history, symptoms and, where required, additional investigations.
Our private blood test services support general health screening and information provision. They do not substitute for advice given by your GP or specialist.
Biomarker information for B12 Blood Test blood test
Vitamin B12 is important for production of red blood cells which carry oxygen around the body. B12 is also involved in metabolism and the nervous system and prolonged lack of vitamin B12 may cause nerve damage.
Our Reviews
What does the B12 Blood Test blood test involve?
This blood test is just like a standard blood test.
You will be asked to uncover you left or right arm and suitable vein is found. A tourniquet will be placed and tightened around your upper arm allowing the veins to swell and a needle will be placed into your vein. A small quantity of blood is then drawn into tubes. Once the procedure is complete a small plaster will be placed onto the site which can be removed after a few hours.
How do I prepare
- The blood test requires access to the area of interest, therefore, it is recommended to wear loose clothing to facilitate this process.
- Wear short sleeves or clothing that allows easy access to your arm for the blood draw.
- Vitamin B12 supplements (tablets, sublingual drops, injections) can temporarily raise your blood levels.
- Your GP may ask you to skip B12 supplements for a short period before the test (often 24 hours) to avoid skewed results.
- If you are unsure about the preparation, please contact us for further information.
How to find us
We pride ourselves on providing the best quality service we can which is why we are trusted by GP's, doctors, physiotherapists, midwives and many other healthcare professionals.
Our mission of better quality healthcare for everyone is at the heart of everything we do and drives us to do the best we can for each and every patient that we see. Our team of experts have years of experience and are fully registered and regulated meaning you are in safe hands with us.
B12 Blood Test FAQ's
Important Notes
- We may require details of your GP / Health Care Professional before or at the time of the test.
- Our London East clinic is located on the first floor, up one flight of stairs. Please note that we don’t have a lift available at this location.
- Blood results require interpretation. All results should be interpreted by your regular health care professional / GP.
- All of our first-line tests are optional and provided on a self-referral basis. You must be aged 16 years or over to use this service. If you have an existing medical condition, are undergoing treatment, or have any concerns about whether this test is appropriate for you, we recommend that you consult your GP or healthcare professional before booking.
- We kindly ask that you inform us of any specific requirements, reasonable adjustments, cultural considerations, or practitioner preferences before your appointment. Whilst we will make every reasonable effort to accommodate requests, this may not always be possible at short notice or subject to staff availability.