Vitamin B12

Answer 1

Definition

Vitamin B12 is a water-soluble vitamin. Water-soluble vitamins dissolve in water. After the body uses these vitamins, leftover amounts leave the body through the urine.

Typically, water-soluble vitamins can not be stored by the body. Vitamin B12 is special, because the body can store it for years in the liver.

Alternative Names

Cobalamin; Deficiency - B12

Function

Vitamin B12, like the other B vitamins, is important for metabolism. It helps in the formation of red blood cells and in the maintenance of the central nervous system.

Food Sources

Vitamin B12 is found in eggs, meat, poultry, shellfish, milk, and milk products.

Side Effects

Vitamin B12 deficiencies occur when the body is unable to properly use the vitamin. Pernicious anemia can make the body unable to absorb vitamin B12 from the intestinal tract.

Because vitamin B12 comes primarily from animal products, people who follow a strict vegetarian or vegan diet and do not consume eggs or dairy products may require vitamin B12 supplements. (Non-animal sources of vitamin B12 exist but are highly variable in their B12 content. They are considered unreliable sources of the vitamin.)

Those who had surgery on specific parts of the small intestine or stomach are also prone to a deficiency if they do not take B12 supplements.

Low levels of B12 can cause anemia, numbness or tingling in the arms and legs, weakness, and loss of balance.

Recommendations

The Food and Nutrition Board at the Institute of Medicine recommends the following dietary intake for vitamin B 12:

Infants

• 0 - 6 months: 0.4 micrograms per day (mcg/day)
• 7 - 12 months: 0.5 mcg/day

Children

• 1 - 3 years: 0.9 mcg/day
• 4 - 8 years: 1.2 mcg/day
• 9 - 13 years: 1.8 mcg/day

Adolescents and Adults

• Males and females age 14 and older: 2.4 mcg/day

Specific recommendations depend on age, gender, and other factors (such as pregnancy). Women who are pregnant or producing breast milk (lactating) need higher amounts. Ask your health care provider which amount is best for you.

The best way to get the daily requirement of essential vitamins is to eat a balanced diet that contains a variety of foods from the food guide pyramid.

References

Rakel D, ed. Integrative Medicine. 2nd ed. Philadelphia, Pa: Saunders Elsevier; 2007.

Hamrick I, Counts SH. Vitamin and mineral supplements. Wellness and Prevention. December 2008:35(4);729-747.

Mason JB. Vitamins, trace minerals, and other micronutrients. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 237.

Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes: Thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline. Washington, DC: National Academy Press; 1998.

Answer 2

Definition

Vitamin B12 is a water-soluble vitamin. Water-soluble vitamins dissolve in water. After the body uses these vitamins, leftover amounts leave the body through the urine.

The body can store vitamin B12 for years in the liver.

Alternative Names

Cobalamin; Cyanocobalamin

Function

Vitamin B12, like the other B vitamins, is important for metabolism. It helps in the formation of red blood cells and in the maintenance of the central nervous system.

Food Sources

Vitamin B12 is found in:

• Eggs
• Fortified foods such as soymilk
• Meat
• Milk and milk products
• Organ meats (liver and kidney)
• Poultry
• Shellfish

The body absorbs animal sources of vitamin B12 much better than plant sources. Non-animal sources of vitamin B12 vary in their amount of B12. They are not thought to be reliable sources of the vitamin.

Side Effects

A lack of vitamin B12 (B12 deficiency) occurs when the body does not get or is unable to absorb the amount of vitamin that the body needs.

• Many people over age 50 lose the ability to absorb vitamin B12 from foods.
• People who follow a strict vegetarian or vegan diet and do not consume eggs or dairy products may need vitamin B12 supplements.
• Those who have had gastrointestinal surgery, such as weight loss surgery, lose the ability to absorb vitamin B12.
• People who have digestive disorders, such as celiac disease or Crohn's disease, may not absorb enough vitamin B12.

Low levels of B12 can cause:

• Anemia
• Loss of balance
• Numbness or tingling in the arms and legs
• Weakness

See also:

• Megaloblastic anemia
• Pernicious anemia

Recommendations

The best way to meet your body's vitamin B12 needs is to eat a wide variety of animal products.

For people who do not eat animal products, vitamin B12 can be found in:

• Almost all multivitamins. Vitamin B12 is better absorbed by the body when it is taken along with other B vitamins, such as niacin, riboflavin, vitamin B6, and magnesium.
• A form of vitamin B12 can be given by injection.
• Another prescription form of vitamin B12 is a nasal gel (for use in the nose).
• Vitamin B12 is also available in a form that dissolves under the tongue (sublingual), but the multivitamin pill form works as well.

The Recommended Dietary Allowance (RDA) for vitamins reflects how much of each vitamin most people should receive on a daily basis. The RDA for vitamins may be used as goals for each person.

How much of each vitamin you need depends on your age and gender. Other factors, such as pregnancy and illnesses, are also important. Women who are pregnant or breast-feeding need higher amounts. Ask your health care provider which amount is best for you.

Dietary Reference Intakes for vitamin B12:

Infants (adequate intake)

• 0 - 6 months: 0.4 micrograms per day (mcg/day)
• 7 - 12 months: 0.5 mcg/day

Children

• 1 - 3 years: 0.9 mcg/day
• 4 - 8 years: 1.2 mcg/day
• 9 - 13 years: 1.8 mcg/day

Adolescents and Adults

• Males and females age 14 and older: 2.4 mcg/day

References

Escott-Stump S, ed. Nutrition and Diagnosis-Related Care. 6th ed. Philadelphia, Pa: Lippincott Williams & Wilkins; 2008.

Sarubin Fragaakis A, Thomson C. The Health Professional's Guide to Popular Dietary Supplements. 3rd ed. Chicago, Il: American Dietetic Association; 2007.

Institute of Medicine. Food and Nutrition Board. Dietary Reference Intakes: Thiamin, riboflavin, niacin, vitamin B6, folate, vitamin B12, pantothenic acid, biotin, and choline. Washington, DC: National Academy Press; 1998.

Reviewed By

Review Date: 02/15/2011

Alison Evert, MS, RD, CDE, Nutritionist, University of Washington Medical Center Diabetes Care Center, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

Answer 3

Vitamin B12 is responsible for the smooth functioning of the nervous system and converting food into cellular energy. More than 90% of Indians, especially Vegetarians are deficient in B12, so you are not alone if you feel brain fog & low energy. Rasayanam brings you Plant-based Vitamin B12 made with the best quality Wheatgrass, Moringa, Amla, & Beetroot so do not have to rely on Allopathic chemically synthesized products. This is a 100% Natural & Vegetarian product. Even our capsule shells are made of safe & organic rice starch.

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Answer 4

The Vitamin B complex. Vitamin B is energy. Found in Gatorade/Poweraid easily.

Answer 5

The chemical formula of vitamin B12 is C63H88CoN14O14P. Vitamin B12 contain cobalt - it is a cobalamin.