Vitamin B12 is one of the 13 essential vitamins your body needs for cell function, growth and development. Your body gets vitamins from food, or dietary supplements, and stores fat-soluble vitamins in fatty tissue. Water-soluble vitamins are used immediately or excreted from the body through urine. Unlike other water-soluble vitamins, your body can store B12 in the liver for years.
B Vitamins
Vitamin B12 is one of the five B-vitamins your body uses to process food into energy and form red blood cells. The B vitamins include B1, also known as thiamin; B2, or riboflavin; B3, or niacin; B5, known as pantothenic acid; B6; B7, or biotin; B12; and folic acid. The B vitamins are found in the protein of foods such as meat, poultry, fish, eggs, dairy products, peas, beans and leafy green vegetables. Manufacturers add B vitamins to some foods, such as breads and cereals.
Vitamin B12
Vitamin B12, which contains the mineral cobalt, exists in a variety of forms, some of which are important to human metabolism. Vitamin B12 is known by many names, including B complex, cobalamins, bedumil, cyanocobalamin and hydroxocobalamin. Vitamin B12, which binds to the protein in foods, is released into your body during digestion and, after binding with the substance intrinsic factor, is absorbed into your bloodstream. B12 maintains your central nervous system by making red blood cells, nerve cells and DNA.
Deficiency
B12 deficiency is rare since the body stores the vitamin for years. According to the Mayo Clinic, people at increased risk for B12 deficiency include the elderly, breastfed infants, vegans, vegetarians and people with conditions that require increased levels of vitamin B12, such as pregnant women and people with kidney or liver disease. Pernicious anemia, a condition that prevents absorption of B12 from the digestive track, can cause a deficiency. Vitamin B12 deficiency can cause megaloblastic amemia, a condition characterized by abnormally large red blood cells. Vitamin B12 deficiency is linked to Alzheimer's disease and breast cancer and can cause various psychiatric and neurologic symptoms.
Recommended Dietary Allowances
Based on the RDA, or recommended dietary allowance, individuals over age 14 should get 2.4 mg daily of dietary vitamin B12, according to the National Institutes of Health. The RDA for pregnant females is 2.6 mg daily and 2.8 mg for lactating females. Pediatricians use the designation "adequate intake," or AI, for vitamin B12 levels in infants up to 1 year old, for whom recommendations range from 0.4 to 0.5 mg. The vitamin B12 RDA for children ages 1 to 3 is 0.9 mg. For children ages 4 to 8, the RDA is 1.2 mg, and for children 9 to 12 years old, the RDA is 1.2 mg.
Supplemental Forms
Doctors recommend or prescribe supplemental forms of vitamin B12 based on need. Dietary supplements are available in substances your body easily converts to more usable forms. Some people take lozenges or tablets that are placed under the tongue. Your doctor might prescribe B12 muscular injections or a gel B12 form administered through the nose. The various vitamin B12 forms are equal in terms of absorption. Individuals who take a 500 mcg vitamin B12 oral supplement absorb only about 10 mcg, according to the National Institutes of Health. Intrinsic factor determines the amount of vitamin B12 your body can absorb.
Tips and Warnings
The 13 essential vitamins are: A, the five B vitamins, C, D, E, K, pantothenic acid, biotin and folate. See your doctor before taking vitamin B12 supplements. Too much of a vitamin can cause toxic levels in your body.
Member Comments