Also Known As: Vitamin B12 Assay, CblC, Vitamin B12 Serum, B12 Assay
What Is A Vitamin B12 (Cobalamin) Test?
A Vitamin B12 (Cobalamin) Test measures the amount of Vitamin B12 in your bloodstream or urine to estimate your body's overall Vitamin B12 stores. Vitamin B12 is one of our body’s essential nutrients for several bodily functions and processes. It also helps with brain health, nerve function, and the formation/production of red blood cells and DNA.
During this test, you can get your blood drawn or give a urine sample so the doctor can check out the levels of methylmalonic acid (MMA), overall Vitamin B12 in your body, homocysteine, and holotranscobalamin (holoTC). The test often gives an accurate reading of MMA and holoTC. Still, lower levels of B12 can be due to temporary infertility in women, permanent nerve damage, declining brain function, memory loss, etc.
Meat eaters and obese people with high food consumption often have excessive Vitamin B12 in their bodies. However, higher levels can indicate leukemia, liver diseases, and even diabetes. Vitamin B12 deficiency, on the other hand, is widespread. Many people, particularly adults and those with intestinal issues, have a hard time absorbing the vitamin from their diet or food supplements. Other people at risk of B12 shortage include those with pregnancy, breastfeeding, heavy alcohol consumption, Crohn's disease, HIV, or AIDS.
What Is The Test Used For?
A vitamin B12 blood test from any diagnostic lab helps diagnose neuropathy and macrocytic anemia. It is also helpful in evaluating and monitoring the treatment plan for vitamin B12 deficiency. Your doctor can use this test to detect B12 deficiency during Pernicious anemia, Folic acid deficiency, megaloblastic anemia, prenatal care, alcoholism, malabsorption of vitamin B12 in the body, and neurological disorders.
Vitamin B12 is required for nerve function, new red blood cells, and tissue/ cellular repair. It is not produced in the human body but instead ingested through fish, poultry, red meat, milk, and other fortified products. Deficiency can occur due to malabsorption or insufficient dietary intake. Symptoms indicating vitamin B12 deficiency are:
Some common causes for vitamin B12 deficiency are:
- Liver diseases
- Excessive use of alcohol
- Celiac disease
- Inflammatory bowel disease
- Cystic fibrosis
- Abnormal heat production, for example, with hyperthyroidism
- Increased vitamin b12 level is uncommon but can be due to:
- Myeloproliferative disorders such as myelogenous leukemia and polycythemia vera
- Liver diseases like hepatitis and cirrhosis
Why And When Do You Need A Vitamin B12 Test?
Your doctor will ask for a vitamin B12 level test to check how much vitamin B12 is present in the body. The test results will help him determine if your symptoms are due to abnormal vitamin B12 levels. You may be required to undergo a vitamin B12 level test if you are showing any of the following:
Vitamin B12 Deficiency
According to different studies and research, up to 20% of people exhibit vitamin B12 deficiency, the sign, and symptoms of which include:
- Sour mouth or tongue
- Difficulty maintaining balance
- Poor memory
- Numbness and tingling of hands and feet
- Fast heartbeat
If you show symptoms of pernicious anemia, your doctor will immediately ask you to undergo a vitamin B12 test. This condition can cause a low level of red blood cells due to your body's inability to absorb vitamin B12 efficiently. Pernicious anemia often influences older adults and people with no intrinsic factor. The symptoms of pernicious anemia include:
- Extreme fatigue
- Loss of appetite
- Weight loss
- Pale skin
High Serum Folate Levels
Another reason you might need this test is high serum folate levels. Serum folate is the level of folic acid in your bloodstream. Higher than normal range can mask the symptoms of vitamin B12 deficiency and make your neurological symptoms worse.
What Kind Of Sample Is Required For The Test?
For the vitamin B12 test, a lab technician or nurse will draw a blood sample from a vein in your arm. After cleaning the site with antiseptic cotton, they will insert the needle in a suitable vein and collect sufficient blood in a test tube or vial. After collecting your blood, the sample will be sent to the laboratory for further analysis. The entire process is very easy and only takes about 5 to 6 minutes.
Do You Need To Prepare For The Test?
Before you can test for vitamin B12, your doctor or health care provider will advise you not to eat or drink for at least 6-8 hours. You need to make sure that you are well hydrated on the days succeeding the test. It is also important to note that certain medicines and pregnancy can also affect your test results. Therefore it is also important to consult with your Healthcare provider regarding which medicines and supplements to stop taking.
Are There Any Risks To This Test?
Vitamin B12 test is a standard blood test with little to almost zero risks involved. You might experience slight pain or bruise at the puncture site, but usually, the symptoms are mild and go away on their own quickly.
What Do The Test Results Mean?
The vitamin B12 test results level may differ from one laboratory to another. Therefore you must discuss your test results and their appropriate interpretation with your doctor. The test results with low levels of vitamin B12 (below 200 pg/ml) indicate that you might have:
- Vitamin B12 deficiency
- Pernicious anemia
- Overactive thyroid
- If you have low vitamin B12 levels, you are susceptible to experiencing some neurological symptoms.
The test results with abnormally high levels of vitamin B12 (above 900 pg/ml) can be due to:
- Kidney problems
- Certain forms of leukemia
Besides suggesting a vitamin B12 test, your doctor can also ask you to undergo a methylmalonic acid test to help detect vitamin B12 deficiency in its early stages.
Related Tests: Vitamin C Blood Test, Vitamin B5 Blood Test, Vitamin B7 Blood Test, Vitamins Blood Test Panel, Vitamin Deficiency, and Wellness Blood Test Panel
Frequently ordered together
Folate (Folic acid)
Vitamin B12 and Folic Acid
Biotin (Vitamin B7)
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