Vitamin B12

Written by National Institutes of Health

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Detailed information about vitamin B12, vitamin B12 deficiency and vitamin B12 supplement.

Dietary Supplement Fact Sheet: Vitamin B12

Table of Contents

What is vitamin B12?

Vitamin B12 is also called cobalamin because it contains the metal cobalt. This vitamin helps maintain healthy nerve cells and red blood cells [1-4]. It is also needed to help make DNA, the genetic material in all cells [1-4]. Vitamin B12 is bound to the protein in food. Hydrochloric acid in the stomach releases B12 from proteins in foods during digestion. Once released, vitamin B12 combines with a substance called gastric intrinsic factor (IF). This complex can then be absorbed by the intestinal tract.

What foods provide vitamin B12?

Vitamin B12 is naturally found in animal foods including fish, meat, poultry, eggs, milk, and milk products. Fortified breakfast cereals are a particularly valuable source of vitamin B12 for vegetarians [5-7]. Table 1 lists a variety of food sources of vitamin B12.

Table 1: Selected food sources of vitamin B12 [5]

Food	Micrograms (Î¼g) per serving	Percent DV*
Mollusks, clam, mixed species, cooked, 3 ounces	84.1	1400
Liver, beef, braised, 1 slice	47.9	780
Fortified breakfast cereals, (100%) fortified), ¾ cup	6.0	100
Trout, rainbow, wild, cooked, 3 ounces	5.4	90
Salmon, sockeye, cooked, 3 ounces	4.9	80
Trout, rainbow, farmed, cooked, 3 ounces	4.2	50
Beef, top sirloin, lean, choice, broiled, 3 ounces	2.4	40
Fast Food, Cheeseburger, regular, double patty & bun, 1 sandwich	1.9	30
Fast Food, Taco, 1 large	1.6	25
Fortified breakfast cereals (25% fortified), ¾ cup	1.5	25
Yogurt, plain, skim, with 13 grams protein per cup, 1 cup	1.4	25
Haddock, cooked, 3 ounces	1.2	20
Clams, breaded & fried, ¾ cup	1.1	20
Tuna, white, canned in water, drained solids, 3 ounces	1.0	15
Milk, 1 cup	0.9	15
Pork, cured, ham, lean only, canned, roasted, 3 ounces	0.6	10
Egg, whole, hard boiled, 1	0.6	10
American pasteurized cheese food, 1 ounces	0.3	6
Chicken, breast, meat only, roasted, ½ breast	0.3	6

*DV = Daily Value. DVs are reference numbers developed by the Food and Drug Administration (FDA) to help consumers determine if a food contains a lot or a little of a specific nutrient. The DV for vitamin B12 is 6.0 micrograms (Î¼g). Most food labels do not list a food's vitamin B12 content. The percent DV (%DV) listed on the table indicates the percentage of the DV provided in one serving. A food providing 5% of the DV or less is a low source while a food that provides 10-19% of the DV is a good source. A food that provides 20% or more of the DV is high in that nutrient. It is important to remember that foods that provide lower percentages of the DV also contribute to a healthful diet. For foods not listed in this table, please refer to the U.S. Department of Agriculture's Nutrient Database Web site: http://www.nal.usda.gov/fnic/cgi-bin/nut_search.pl.

References