Table of ContentsView AllTable of ContentsWho Should Get Tested?How to PrepareResultsPotential RisksHome TestsNext Steps
Table of ContentsView All
View All
Table of Contents
Who Should Get Tested?
How to Prepare
Results
Potential Risks
Home Tests
Next Steps
A vitamin B12 blood test is a reliable way to determine if you have adequate levels of this crucial nutrient.Vitamin B12 is essential for nerve function, making red blood cells, and helping your body make DNA. If you don’t get enough B12, it can cause health problems like anemia, tingling in your hands and feet, and heart palpitations.While a blood test is the most common method, urine tests are also available, though they may not provide the same level of accuracy.
Healthcare providers typically recommend a vitamin B12 test if you exhibit symptoms of deficiency or have risk factors such as specific dietary habits or medical conditions.
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Who Should Get a Vitamin B12 Blood Test
A vitamin B12 blood test is often recommended for:
Consult your healthcare provider to understand what these ranges mean for you, as lab standards may vary slightly.
Preparing for a vitamin B12 blood test is straightforward but essential for accurate results:
Medications that may affect the test include:
Do not stop any medications before talking with your healthcare provider.
How to Interpret the Results
Normal vitamin B12 levels range from 160 to 950 pg/mL. Values within this range indicate sufficient vitamin B12 to support bodily functions. Keep in mind that some labs use different measurements; talk to your healthcare provider about what your specific test results mean.
Low Levels
Elevated Levels
Levels above 900 pg/mL are less common as it is usually removed via urine, but may indicate:
Discuss your results with your healthcare provider to account for individual health conditions.
The risks associated with a vitamin B12 blood test are minimal. These include:
If you have concerns about these risks, discuss them with your healthcare provider before the test.
What About Home Tests?
At-home test kits for vitamin B12 are available and often involve collecting a urine sample. While convenient, they have limitations:
Urine MMA tests are used to check for a vitamin B12 deficiency, which can cause high MMA levels in the urine. There are two types of urine MMA tests: a 24-hour test and a random test. The 24-hour test requires you to collect all your urine over 24 hours, giving a complete picture of your MMA levels, while a random test only needs one sample from any time of the day, making it quicker but less detailed.
Home tests can be a good starting point but should not replace clinical evaluation.
Next Steps If You Have Abnormal Results
Low B12 Levels
If your B12 levels are low, consider the following:
Certain medications can affect vitamin B12 absorption and levels, leading to potential deficiencies. Those taking these medications should discuss their B12 status with their healthcare provider:
Elevated B12 Levels
Vitamin B12 has a low risk of toxicity. Even when taken in large amounts, it is typically considered safe since the body does not retain excess B12.
Monitoring
After testing vitamin B12 levels, it’s important to monitor them according to your healthcare provider’s recommendation, especially if deficiencies are identified or if you’re taking medications that affect B12 absorption.
Ongoing monitoring helps ensure levels stay within a healthy range and can prevent potential long-term complications, such as nerve damage or cognitive issues. Regular check-ups with your healthcare provider can help adjust treatment plans as needed, ensuring optimal B12 levels for overall health.
Summary
A vitamin B12 blood test is a valuable tool for assessing your B12 levels, whether you’re experiencing symptoms of deficiency or have risk factors. It provides a clear picture of whether your levels are low, normal, or elevated, helping guide treatment and dietary changes. While at-home test kits offer convenience, professional blood tests remain the gold standard for accuracy and comprehensive evaluation. If your results are abnormal, work with your healthcare provider to determine the best course of action.
9 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Medline Plus.Vitamin B12 level.National Institutes of Health.Vitamin B12.Medline Plus.Methylmalonic acid (MMA) test.UCSF Health.Vitamin B12 level.Medline Plus.Fasting for a blood test.Wu HHL, Wang AYM.Vitamin B12 and chronic kidney disease. In:Vitamins and Hormones. Vol 119. Elsevier; 2022:325-353. doi:10.1016/bs.vh.2022.01.011Medline Plus.Polycythemia vera.Vashi P, Edwin P, Popiel B, Lammersfeld C, Gupta D.Methylmalonic acid and homocysteine as indicators of vitamin b-12 deficiency in cancer.PLoS ONE. 2016;11(1):e0147843. doi:10.1371/journal.pone.0147843Familydoctor.org.Vitamin B12 deficiency: recognition and management.
9 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Medline Plus.Vitamin B12 level.National Institutes of Health.Vitamin B12.Medline Plus.Methylmalonic acid (MMA) test.UCSF Health.Vitamin B12 level.Medline Plus.Fasting for a blood test.Wu HHL, Wang AYM.Vitamin B12 and chronic kidney disease. In:Vitamins and Hormones. Vol 119. Elsevier; 2022:325-353. doi:10.1016/bs.vh.2022.01.011Medline Plus.Polycythemia vera.Vashi P, Edwin P, Popiel B, Lammersfeld C, Gupta D.Methylmalonic acid and homocysteine as indicators of vitamin b-12 deficiency in cancer.PLoS ONE. 2016;11(1):e0147843. doi:10.1371/journal.pone.0147843Familydoctor.org.Vitamin B12 deficiency: recognition and management.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Medline Plus.Vitamin B12 level.National Institutes of Health.Vitamin B12.Medline Plus.Methylmalonic acid (MMA) test.UCSF Health.Vitamin B12 level.Medline Plus.Fasting for a blood test.Wu HHL, Wang AYM.Vitamin B12 and chronic kidney disease. In:Vitamins and Hormones. Vol 119. Elsevier; 2022:325-353. doi:10.1016/bs.vh.2022.01.011Medline Plus.Polycythemia vera.Vashi P, Edwin P, Popiel B, Lammersfeld C, Gupta D.Methylmalonic acid and homocysteine as indicators of vitamin b-12 deficiency in cancer.PLoS ONE. 2016;11(1):e0147843. doi:10.1371/journal.pone.0147843Familydoctor.org.Vitamin B12 deficiency: recognition and management.
Medline Plus.Vitamin B12 level.
National Institutes of Health.Vitamin B12.
Medline Plus.Methylmalonic acid (MMA) test.
UCSF Health.Vitamin B12 level.
Medline Plus.Fasting for a blood test.
Wu HHL, Wang AYM.Vitamin B12 and chronic kidney disease. In:Vitamins and Hormones. Vol 119. Elsevier; 2022:325-353. doi:10.1016/bs.vh.2022.01.011
Medline Plus.Polycythemia vera.
Vashi P, Edwin P, Popiel B, Lammersfeld C, Gupta D.Methylmalonic acid and homocysteine as indicators of vitamin b-12 deficiency in cancer.PLoS ONE. 2016;11(1):e0147843. doi:10.1371/journal.pone.0147843
Familydoctor.org.Vitamin B12 deficiency: recognition and management.
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