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Vitamin B12

By Shereen Jegtvig, About.com

Updated: March 17, 2009

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Steak

Vitamin B12 is found in foods of animal origin.

Photo © Greg Nicholas
Definition: Vitamin B12, or cobalamin, is a member of the water-soluble family of B complex vitamins. It's required for normal function of nerve cells, DNA production and B12 is needed for your body to make an adequate number of blood cells.

Daily Requirements

1 to 3 years 0.9 mcg per day
4 to 8 years 1.2 mcg per day
9 to 13 years 1.8 mg per day
14+ years 2.4 mg per day

Vitamin B12 supplements have been recommended for improving cognitive skills and to boost energy. However, research hasn't provided sufficient evidence for these recommendations. Vitamin B12 supplements will reduce homocysteine levels in your blood, though supplementation does not appear to reduce the risk of cardiovascular disease.

Vitamin B12 is found naturally in meats, poultry, seafood, eggs, and dairy products. Supplementation should not be necessary for healthy adults, except for vegans, as vitamin B12 is only found in animal products. People with medical disorders such as pernicious anemia, celiac disease, atrophic gastritis or Crohn's disease may require supplemental vitamin B12 (often taken as shots).

Also Known As: Cobalamin

Sources:

Office of Dietary Supplements. "Dietary Supplement Fact Sheet: Vitamin B12." NIH. Updated 08/2007.

Food and Nutrition Board. "Dietary Reference Intakes." Institute of Medicine. Published 2004.

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