Table of ContentsView AllTable of ContentsHow Much Do You Need?Signs of DeficiencyDiagnosing a DeficiencyOlder Adults and B12How B12 Can HelpDaily SupplementationOther Sources of B12
Table of ContentsView All
View All
Table of Contents
How Much Do You Need?
Signs of Deficiency
Diagnosing a Deficiency
Older Adults and B12
How B12 Can Help
Daily Supplementation
Other Sources of B12
Vitamin B12, also known as cobalamin, is an important nutrient in food, especially seafood, animal products, and foods fortified with vitamin B12.This vitamin is involved in many body functions, including producing red blood cells (RBCs), maintaining neurological health, and in the body’s energy-producing processes.
While vitamin B12 may help maintain energy, concentration, memory, and mood levels—clinical evidence suggests that only those who have avitamin B12 deficiencybenefit from supplementing with this nutrient.
It takes at least a few weeks for this vitamin deficiency to cause symptoms or for you to feel the benefits of supplementation when making up for a deficit.Along with vitamin B12, diet and exercise also affect your overall energy level.
How Much Vitamin B12 Do You Need?
Supplement Safety
In the United States, the Food and Drug Administration (FDA) does not regulate dietary supplements the way it regulates prescription medications. As a result, some supplement products may not contain the ingredients listed on the label.
Can You Tell If You Have a Vitamin B12 Deficiency?
Therefore, even if you are experiencing symptoms, you should have diagnostic tests so that your healthcare providers can determine what’s causing them.
Anemia (a low number of healthy red blood cells) causes many of thesymptomsof vitamin B12 deficiency.Peripheral neuropathy, which is impaired function in nerves outside the brain and spinal cord, can result from vitamin B12 deficiency and may lead to early symptoms of this condition.
Symptoms and effects of vitamin B12 deficiency include:
Long-term vitamin B12 deficiency can cause other health consequences, which may include a higher-than-average risk of heart disease, stroke, spinal cord damage, ordementia.
How a B12 Deficiency Is Diagnosed
When giving a physical examination, your healthcare provider can identify signs that could indicate you have a vitamin B12 deficiency. These signs include pale skin, a rapid heart rate, and decreased hand and foot sensations.
However, these signs are not specific to vitamin B12 deficiency and could also indicate health conditions unrelated to vitamin B12.
Several blood tests can help identify vitamin B12 deficiency:
Other tests can examine the health consequences of vitamin B12 deficiency. For example, due to anemia, your heart rate can be faster than usual.Nerve conduction studiescan be used to diagnose peripheral neuropathy, which may occur due to vitamin B12 deficiency.
Pernicious Anemia and Vitamin B12 DeficiencyPernicious anemiais a condition that interferes with the body’s absorption of vitamin B12. This type of anemia causes vitamin B12 deficiency. Consequently, vitamin B12 deficiency causes macrocytic anemia due to impaired RBC production.
Pernicious Anemia and Vitamin B12 Deficiency
Pernicious anemiais a condition that interferes with the body’s absorption of vitamin B12. This type of anemia causes vitamin B12 deficiency. Consequently, vitamin B12 deficiency causes macrocytic anemia due to impaired RBC production.
Do Older Adults Need More Vitamin B12?
Older adults do not need more vitamin B12 than anyone else over age 18,but certain health factors increase the risk of vitamin B12 deficiency in older adults. With age, it is more common for people to take medications or to have medical diseases that could interfere with vitamin B12 absorption.
Additionally, having another underlying medical condition, such as peripheral neuropathy or dementia, could make the effects of vitamin B12 deficiency add up with these other underlying disorders, worsening your overall symptoms.
What Conditions Can Vitamin B12 Help?
Benefits of Vitamin B12 and How to Get Enough of It
Should You Supplement Every Day?
Usually, people do not need to takevitamin supplementsif they aren’t deficient. If you are not deficient in vitamin B12, you are getting an adequate amount in your diet, absorbing it properly, and there’s no need to take a supplement.
However, vitamin B12 supplements are not harmful if taken in moderation, so taking them as part of a multivitamin is fine if that’s convenient for you.
Some people have trouble absorbing this vitamin due to disease, gastric surgery, or medication. If this is the case with you, you may need intramuscular injections (injections through a muscle) rather than pills.
Timing of Vitamin B12
You can get vitamin B12 frommany different foods and drinks, andmost of the sources are either animal products or foods fortified with vitamin B12. If you follow a vegan diet, plan how to get enough vitamin B12 in your diet through food, or may you need to take a supplement.
Some foods that provide vitamin B12 are:
Foods that don’t naturally contain vitamin B12, such as breakfast cereals and nutritional yeast, may be fortified with this vitamin.You don’t need to worry aboutgetting too much vitamin B12 in your dietas your body eliminates excess in the urine.
Summary
Vitamin B12 is an important nutrient that your body uses for many functions. This vitamin is important to RBC production, your body’s energy production, and your nervous system health. If you are low in vitamin B12, you may feel tired, experience brain fog, or have decreased sensation in your hands and feet.
It takes at least several weeks for this vitamin to carry out its chemical functions in the body, so supplements will not immediately increase your energy. You might not feel the effects of correcting your vitamin B12 deficiency until at least a few weeks after you start increasing your dietary intake, taking a supplement, or getting an injection.
Taking vitamin B12 every day is safe, but if you are not deficient, you don’t need to take a supplement, and taking extra amounts will not provide added benefits.
B12 for Fibromyalgia and Chronic Fatigue Syndrome
6 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.Office of Dietary Supplements.Vitamin B 12 fact sheet for consumers.Baghel M, Shi SL, Patel H, Velagapudi V, Ali AM, Yadav VK.Taurine/chenodeoxycholic acid ratio as a potential serum biomarker for low vitamin B12levels in humans.Br J Nutr. 2024;132(6):712-724. doi:10.1017/S0007114524002022Langan RC, Goodbred AJ.Vitamin B12 deficiency: recognition and management.Am Fam Physician.2017;96(6):384-389Office of Dietary Supplements.Vitamin B 12 fact sheet for health professionals.Temova Rakuša Ž, Roškar R, Hickey N, Geremia S.Vitamin B12in foods, food supplements, and medicines-a review of Its role and properties with a focus on its stability.Molecules. 2022;28(1):240. doi:10.3390/molecules28010240Koeder C.Toward supplementation guidelines for vegan complementary feeding.Food Sci Nutr.2024;12(12):10962-10971. doi:10.1002/fsn3.4565
6 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.Office of Dietary Supplements.Vitamin B 12 fact sheet for consumers.Baghel M, Shi SL, Patel H, Velagapudi V, Ali AM, Yadav VK.Taurine/chenodeoxycholic acid ratio as a potential serum biomarker for low vitamin B12levels in humans.Br J Nutr. 2024;132(6):712-724. doi:10.1017/S0007114524002022Langan RC, Goodbred AJ.Vitamin B12 deficiency: recognition and management.Am Fam Physician.2017;96(6):384-389Office of Dietary Supplements.Vitamin B 12 fact sheet for health professionals.Temova Rakuša Ž, Roškar R, Hickey N, Geremia S.Vitamin B12in foods, food supplements, and medicines-a review of Its role and properties with a focus on its stability.Molecules. 2022;28(1):240. doi:10.3390/molecules28010240Koeder C.Toward supplementation guidelines for vegan complementary feeding.Food Sci Nutr.2024;12(12):10962-10971. doi:10.1002/fsn3.4565
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.
Office of Dietary Supplements.Vitamin B 12 fact sheet for consumers.Baghel M, Shi SL, Patel H, Velagapudi V, Ali AM, Yadav VK.Taurine/chenodeoxycholic acid ratio as a potential serum biomarker for low vitamin B12levels in humans.Br J Nutr. 2024;132(6):712-724. doi:10.1017/S0007114524002022Langan RC, Goodbred AJ.Vitamin B12 deficiency: recognition and management.Am Fam Physician.2017;96(6):384-389Office of Dietary Supplements.Vitamin B 12 fact sheet for health professionals.Temova Rakuša Ž, Roškar R, Hickey N, Geremia S.Vitamin B12in foods, food supplements, and medicines-a review of Its role and properties with a focus on its stability.Molecules. 2022;28(1):240. doi:10.3390/molecules28010240Koeder C.Toward supplementation guidelines for vegan complementary feeding.Food Sci Nutr.2024;12(12):10962-10971. doi:10.1002/fsn3.4565
Office of Dietary Supplements.Vitamin B 12 fact sheet for consumers.
Baghel M, Shi SL, Patel H, Velagapudi V, Ali AM, Yadav VK.Taurine/chenodeoxycholic acid ratio as a potential serum biomarker for low vitamin B12levels in humans.Br J Nutr. 2024;132(6):712-724. doi:10.1017/S0007114524002022
Langan RC, Goodbred AJ.Vitamin B12 deficiency: recognition and management.Am Fam Physician.2017;96(6):384-389
Office of Dietary Supplements.Vitamin B 12 fact sheet for health professionals.
Temova Rakuša Ž, Roškar R, Hickey N, Geremia S.Vitamin B12in foods, food supplements, and medicines-a review of Its role and properties with a focus on its stability.Molecules. 2022;28(1):240. doi:10.3390/molecules28010240
Koeder C.Toward supplementation guidelines for vegan complementary feeding.Food Sci Nutr.2024;12(12):10962-10971. doi:10.1002/fsn3.4565
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.Cookies SettingsAccept All Cookies
By clicking “Accept All Cookies”, you agree to the storing of cookies on your device to enhance site navigation, analyze site usage, and assist in our marketing efforts.
Cookies SettingsAccept All Cookies
