Vitamin B12 Test

A vitamin B12 test measures the levels of vitamin B12 in the blood. Vitamin B12, also known as cobalamin, is a water-soluble vitamin that plays a key role in the normal functioning of the brain and nervous system, as well as in the formation of red blood cells.

A vitamin B12 test is typically ordered by a healthcare provider if a person is experiencing symptoms of a vitamin B12 deficiency, such as fatigue, weakness, numbness or tingling in the hands and feet, memory problems, and difficulty concentrating. It can also be ordered as part of a routine health check-up or to monitor the effectiveness of B12 supplementation.

A vitamin B12 test requires a blood sample, which is usually collected by a healthcare provider through a simple blood draw. The sample is then sent to a laboratory for analysis, and results are typically available within a few days.

Normal levels of vitamin B12 in the blood typically range from 200 to 900 picograms per milliliter (pg/mL). Levels below 200 pg/mL are considered low and may indicate a vitamin B12 deficiency, which can be treated with B12 supplements or dietary changes. High levels of vitamin B12 in the blood are less common and may be a sign of certain medical conditions, such as liver or kidney disease.