The Vitamin B12 test measures the level of Vitamin B12 (cobalamin) in the blood, an essential nutrient crucial for maintaining healthy nerve cells and blood cells. Vitamin B12 also aids in the synthesis of deoxyribonucleic acid (DNA), the genetic material found in every cell of the body. Since the human body cannot produce Vitamin B12 on its own, it needs to obtain it through foods such as meat, eggs, and dairy. In India, approximately 47% of people suffer from Vitamin B12 deficiency, which can lead to macrocytic anemia, a condition that can cause neuropathy, resulting in tingling or numbness in the hands and feet. Therefore, testing Vitamin B12 levels is important to prevent any potential complications and ensure overall health.

The fundamentals of a Vitamin B12 test are stated below:

• Prerequisites: Fasting is not needed for a Vitamin B12 test.

• Best Time to Get Tested: The Vitamin B12 test can be done at any time of the day.

• Eligibility for Vitamin B12 Test: Vitamin B12 deficiency can affect anyone, regardless of age. So, anyone with symptoms of Vitamin B12 deficiency, for example, weakness, nausea, irritability, etc., can schedule the test.

• Cautions Before Taking Vitamin B12 Test: Certain medications, like proton pump inhibitors, could potentially influence the results of the Vitamin B12 test. Therefore, it is important to inform your doctor of the medicines you are taking before the test.

By preparing with these steps, you can make sure your Vitamin B12 test at home or in a laboratory gives accurate results.

If a full blood count test shows low haemoglobin levels, large red blood cells, or unusual white blood cells, your doctor may recommend a Vitamin B12 test. Other reasons why you might need to do this test include symptoms such as:

• Nausea, vomiting, or diarrhoea

• Reduced appetite

• Extreme fatigue or weakness

• Sensations like tingling or numbness in the hands and feet

• Yellowish skin

• Weight loss

• Mouth or tongue soreness

• Vision issues

• Impaired walking or speech

• Irritability

• Changes in mood and behavior

• Depressed mood

• Difficulty remembering or confusion

Besides these symptoms, you may also need a Vitamin B12 blood test if you:

• Are older than 70 years, as elderly individuals have a higher risk of Vitamin B12 deficiency due to reduced absorption of nutrients in their body.

• Are pregnant, because pregnant women require more B12 to support the growing baby.

• Are dealing with digestive disorders like celiac disease and Crohn's disease, as absorbing Vitamin B12 becomes more challenging for the body with these diseases.

• Follow a plant-based diet (Vitamin B12 is naturally present only in animal products).

• Are taking medications that can cause a reduction in Vitamin B12 levels in the body (e.g., medications for diabetes and peptic ulcers)

• Have Sjögren's syndrome. In this case, the risk of having a Vitamin B12 deficiency increases by over six times.

• Consume excessive alcohol, as it can harm the digestive system and lead to a deficiency in Vitamin B12.

• Are undergoing treatment for malnutrition or a Vitamin B12 deficiency (this test helps assess the effectiveness of treatment).

You may also be recommended to check the level of homocysteine, another marker that can determine B12 deficiency. These additional tests help doctors diagnose a deficiency and the underlying cause, providing a clearer picture for determining treatment.

Vitamin B12 Normal Range

The normal range of Vitamin B12 is 239-931 pg/mL.

Understanding the Test Results

Low Levels

Below normal levels of Vitamin B12 could indicate a deficiency, the causes of which include:

• Lack of intrinsic factor or production of intrinsic antibodies (seen in pernicious anaemia)

• Certain surgical procedures like weight loss surgeries

• Gastrointestinal conditions like atrophic gastritis

• Hereditary disorders like transcobalamin II deficiency

• Conditions that cause reduced absorption of the vitamin such as Crohn's disease, celiac disease, pancreatitis, and resected small bowel

• Dietary deficiencies, particularly in vegetarians

• Fish tapeworm infection

• High homocysteine levels

Moreover, heightened requirements, particularly during pregnancy (final trimester), can also lead to reduced levels of Vitamin B12. Please note that since Vitamin B12 and folate collaborate to support cell function, your doctor may recommend testing your folate level simultaneously.

High levels

An elevated level of Vitamin B12 is rare, as excess amounts are typically excreted in urine. Conditions that may result in increased Vitamin B12 levels include:

• Chronic kidney disease

• Congestive heart failure

• Myelogenous or promyelocytic leukaemia

• Protein malnutrition

• Polycythaemia vera

• Hepatocellular carcinoma

• Metastatic liver disease

• Acute hepatitis

• Cirrhosis

• Drug-induced cholestasis

If you receive unexpected results from your Vitamin B12 test, it's important to consult your doctor for further guidance and interpretation. Arrange your Vitamin B12 test in Bangalore to make sure you get an accurate assessment and reports.