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Vitamin B₁₂

HGIC 4078

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Why We Need It

Vitamin B₁₂ works with folate, another B vitamin, to make DNA, which is the body’s genetic material. Vitamin B₁₂, a water-soluble vitamin, also protects nerve cells from damage and helps keep blood levels of the amino acid homocysteine low. This may help to decrease heart disease risk in some people.

Amounts Needed

Everyone needs vitamin B₁₂. Older adults and strict vegetarians (vegans) should use fortified foods or supplements to ensure that they get enough.

Recommended Daily Intakes of Vitamin B₁₂

	Age	Vitamin B12 (μg/day)
μg = micrograms Source: adapted from the Dietary Reference Intakes series, National Academies Press. Copyright 1997, 1998, 2000, 2001, 2002, 2004, by the National Academies of Sciences.
Infants	birth–6 months	0.4
	6 months–1 year	0.5
Children	1–3 years	0.9
	4–8 years	1.2
Males	9–13 years	1.8
	14 years and over	2.4
Females	9–13 years	1.8
	14 years and over	2.4
	pregnant	2.6
	breastfeeding	2.8

Sources

Vitamin B₁₂ is found naturally only in foods of animal origin like meats, fish, poultry, eggs, and dairy foods. Older people often can not absorb vitamin B₁₂from these foods. However, fortified breads and cereals contain vitamin B₁₂ in a form that is easily absorbed. Check the ingredient list on food labels to see if vitamin B₁₂ has been added. Here is a sample ingredient list from a fortified cereal:

INGREDIENTS: Wheat bran with other parts of wheat, sugar, raisins, whole wheat, partially hydrogenated soybean oil, corn syrup, brown sugar syrup, nonfat milk, salt, honey, vitamin C (sodium ascorbate), vitamin B2 (riboflavin), vitamin B1 (thiamin mononitrate), folic acid, vitamin B12 …

Sources of Vitamin B₁₂

Food	Vitamin B12 (μg per serving)
μg = micrograms oz = ounces
oysters, cooked, 3 oz	30
beef, ground, extra lean, cooked, 3 oz	1.8
tuna, canned, 2 oz	1.6
fortified cereal, 1 serving	1.5
yogurt, plain, 8 oz	1.3
chicken, roasted, 3 oz	0.3

Ways to Retain It

Vitamin B₁₂ is not easily destroyed by cooking. This is good to know, since the main food sources of vitamin B ₁₂ (e.g. meat, fish, and poultry) need to be well cooked. Other sources, like fortified cereals, may not need cooking.

If We Don’t Get Enough

Vitamin B₁₂ deficiency causes pernicious anemia. This affects blood and nerves. With pernicious anemia, the body can’t make normal red blood cells to carry oxygen in the blood. Lack of oxygen makes people weak and tired. Nerve damage can lead to paralysis and death.

Supplements

If you don’t get enough vitamin B₁₂ from foods, you can take a multivitamin supplement. Strict vegetarians who do not eat fortified cereals or fortified soy foods need to take vitamin B₁₂ in a supplement. In addition, older adults often do not absorb vitamin B₁₂ very well. If they don’t get adequate B12 from fortified foods, they need a supplement, also.

For More Information

The Family and Consumer Sciences (FCS) agent at your county Extension office may have more written information and nutrition classes for you to attend. Also, your doctor, health care provider, or a registered dietitian (RD) can provide reliable information.

Reliable nutrition information may be found on the Internet at the following sites:
http://hgic.clemson.edu
http://virtual.clemson.edu/groups/NIRC/
http://www.eatright.org
http://www.nutrition.gov
http://www.nal.usda.gov/fnic

Sources:
1. Bobroff, Linda B. University of Florida Extension. Facts About Vitamin B12 . FCS8701. April 2006. http://edis.ifas.ufl.edu/publications.html
2. National Academies of Sciences. National Academies Press. Dietary Reference Intakes series. 2004.