Vitamin B-12

Cyanocobalamin

ExRx.net > Nutrition > Micronutrients > Vitamin

Functions red blood cell formation involved in synthesis of nucleic acids Deficiency Pernicious anemia Characteristics soluble in water or alcohol unstable in hot alkaline or acid solutions Good Sources Natural beef, pork, chicken liver, kidney milk and dairy products eggs most of vitamin required by humans is synthesized by intestinal bacteria Food Quantity mcg Beef, lean braised flank 3 oz 2.81 Chicken 1/2 breast 0.29 Milk, non-fat 1 cup 0.93 Egg 1 large 0.50 Artificial fortified cereals and soy products Recommended Daily Allowances (RDA) Males (11 yrs. and older) 2.4 mcg 3 mcg Females (11 yrs. and older) 2.4 mcg 3 mcg Pregnant females 4 mcg Lactating females 5 mcg Children 2-5 mcg Infants 1-2 mcg Varied values reflect different references Tolerable Upper Intake Levels (UL) Adults (19 to 50 yrs) not yet determined Intakes above UL may lead to negative health consequences. Supplementation Not usually necessary People who are on strict vegetarian diets may need supplementation. Some elderly people and those with certain food allergies may be deficient in Vitamin B-12 because they lose their ability to absorb it from foods