https://www.mayoclinic.org/drugs-supplements-vitamin-b12/art-20363663
Learn about vitamin B-12, a nutrient that helps form red blood cells, metabolize food and maintain nerve function. Find out how to get enough vitamin B-12 from food or supplements, and what to do if you have a deficiency.

https://www.webmd.com/vitamins/ai/ingredientmono-926/vitamin-b12
Learn about vitamin B12, an essential vitamin for many parts of the body. Find out how it can treat or prevent deficiency, cyanide poisoning, and other conditions, and what are the possible side effects and interactions.

https://www.healthline.com/nutrition/vitamin-b12-benefits
Vitamin B12 is an essential vitamin that supports your blood cells, nerve cells, and DNA. Learn about the health benefits of vitamin B12, the foods that contain it, the symptoms and causes of deficiency, and how to supplement it.

https://my.clevelandclinic.org/health/diseases/22831-vitamin-b12-deficiency
Learn about vitamin B12 deficiency, a condition that happens when your body does not get enough or absorb enough vitamin B12 from your diet. Find out the symptoms, causes, diagnosis, treatment and prevention of this nutritional deficiency.

https://www.verywellhealth.com/vitamin-b12-5083479
Learn about vitamin B12, a water-soluble nutrient that helps your body produce energy, red blood cells, and DNA. Find out the symptoms, causes, and risks of vitamin B12 deficiency, and the foods and supplements that contain it.

https://en.wikipedia.org/wiki/Vitamin_B12
Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. [2] It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, and in both fatty acid and amino acid metabolism. [3]

https://www.webmd.com/diet/vitamin-b12-deficiency-symptoms-causes
Learn about the functions, sources, and recommended intake of vitamin B12, a nutrient that helps make DNA and red blood cells. Find out how to prevent and treat deficiency, which can cause anemia, nerve problems, and vision loss.

https://www.healthline.com/health/vitamin-b12
Learn why vitamin B12 is essential for your health, how to get it from food or supplements, and what happens if you are low on it. Find out the symptoms, causes, and treatments of vitamin B12 deficiency and anemia.

https://ods.od.nih.gov/factsheets/Vitaminb12-HealthProfessional/
Vitamin B12 is a water-soluble vitamin that is naturally present in some foods, added to others, and available as a dietary supplement and a prescription medication. Because vitamin B12 contains the mineral cobalt, compounds with vitamin B12 activity are collectively called cobalamins [ 1 ].

https://ods.od.nih.gov/factsheets/VitaminB12-Consumer/
The amount of vitamin B12 you need each day depends on your age. Average daily recommended amounts for different ages are listed below in micrograms (mcg). Life Stage. Recommended Amount. Birth to 6 months. 0.4 mcg. Infants 7-12 months. 0.5 mcg. Children 1-3 years.

https://www.webmd.com/diet/health-benefits-vitamin-b12
Learn how vitamin B12 helps with DNA, brain, blood, and eye health, and how to avoid deficiency and supplement interactions. Find out the recommended daily intake and food sources of B12.

https://health.clevelandclinic.org/vitamin-b12
The easiest: Vitamin B12 is an essential nutrient that helps your body with creating healthy red blood cells and improving energy levels. way to take in more vitamin B12 is by enriching your diet

https://www.medicalnewstoday.com/articles/219822
Learn about the functions, sources, and symptoms of vitamin B12, a water-soluble vitamin essential for nerve, brain, and blood health. Find out who is at risk of deficiency and how to treat it with supplements or injections.

https://www.healthline.com/nutrition/vitamin-b12-foods
Learn which foods are rich in vitamin B12, a water-soluble vitamin that supports your nerves, DNA, and red blood cells. Find out how much you need, how to absorb it, and which foods are fortified or vegan-friendly sources.

https://www.health.harvard.edu/staying-healthy/the-a-list-for-vitamin-b-12-sources
Learn why vitamin B-12 is important for brain function, DNA production, and blood health, and how to get enough from animal foods or supplements. Find out who is at risk of B-12 deficiency and what are the symptoms and treatments.

https://nutritionsource.hsph.harvard.edu/vitamin-b12/
Vitamin B12 is a water-soluble vitamin, so any unused amount will exit the body through the urine. Generally, up to 1000 mcg a day of an oral tablet to treat a deficiency is considered safe. The Institute of Medicine states "no adverse effects have been associated with excess vitamin B12 intake from food and supplements in healthy individuals."

https://www.nhs.uk/conditions/vitamin-b12-or-folate-deficiency-anaemia/
Learn about the symptoms, causes, diagnosis and treatment of this condition that affects the red blood cells and the nervous system. Find out how to prevent and manage vitamin B12 or folate deficiency with diet, supplements and injections.

https://www.healthline.com/nutrition/vitamin-b12-dosage
Learn about the importance, sources, and recommended dosages of vitamin B12 for different people and situations. Find out how B12 can help prevent deficiency, improve energy, and support your health.

https://www.aafp.org/pubs/afp/issues/2017/0915/p384.html
Learn about the causes, symptoms, diagnosis, and treatment of vitamin B12 deficiency, a common cause of megaloblastic anemia and neurologic problems. Find out who should be screened, how to interpret laboratory tests, and what supplements are recommended.

https://www.ncbi.nlm.nih.gov/books/NBK441923/
Vitamin B12 (cobalamin) is a water-soluble vitamin that is derived from animal products such as red meat, dairy, and eggs. Intrinsic factor is a glycoprotein that is produced by parietal cells in the stomach and is necessary for the absorption of B12 in the terminal ileum. Once absorbed, B12 is used as a cofactor for enzymes that are involved in the synthesis of DNA, fatty acids, and myelin.

https://www.hopkinsmedicine.org/health/conditions-and-diseases/vitamin-b12-deficiency-anemia
Learn about the causes, symptoms, diagnosis, and treatment of vitamin B12 deficiency anemia, a condition that affects red blood cell production. Find out how to prevent and manage this type of anemia with diet, supplements, and lifestyle changes.

https://www.healthline.com/nutrition/vitamin-b12-deficiency-symptoms
Learn about the signs and symptoms of low or deficient B12 levels, such as fatigue, pale skin, headaches, depression, and more. Find out how B12 deficiency is diagnosed and treated, and what foods are rich in B12.

https://www.uptodate.com/contents/treatment-of-vitamin-b12-and-folate-deficiencies
All individuals with documented vitamin B12 and/or folate deficiency should be treated, unless there is a strong reason not to do so (eg, palliative care setting or patient refusal). A number of general principles apply to both vitamin B12 and folate deficiency. These are outlined below and in a 2014 guideline on the diagnosis and treatment of