Vitamin B12 is a water-soluble nutrient that is important to the health of the body and is involved in the metabolism of cells and  affects DNA.  Vitamin B12 comes from dairy products, fish and meat and from plants.   Both types of Vitamin B12 are stored in liver.   In the body, beta-carotene, which is obtained from plants, acts as an antioxidant.

WHAT DOES BETA-CAROTENE HAVE TO DO WITH B12?

Because vitamin B12 contains cobalt, its forms are called cobalamins.   There are two forms of cobalamins – cyanocobalamin and methylcobalamin.  The most common form used in supplements is cyanocobalamin.  Cyanocobalamin is a semi-synthetic form that contains a tiny amount of cyanide, considered by most to not be toxic to the body.  This small amount of cyanide must be discarded by the body before the remaining B12 becomes a form of methylcobalamin and can be used.

Methylcobalamin is a form of B12 that is naturally occurring in the body and is considered by many to be more easily assimilated into the body.  It is much more expensive than cyanocobalamin.

Although vitamin B12 can be taken orally, it is generally most effective when taken by intra-muscular or other injection.

USES IN THE BODY

Vitamin B12 is used by the body:
For treatment of anemia
•    For energy
•    For treatment of numbness in the legs and arms
•    For treatment of a tingling sensation in the legs and arms
•    To assist with sleep problems

SYMPTOMS OF Vitamin B12 DEFICIENCY

The symptoms most commonly associated with Vitamin B12 deficiency are:
•    Fatigue
•    Weakness
•    Constipation
•    Insomnia
•    Depression
•    Confusion
•    Memory problems
Doctors warn that if a person is deficient in B12 for too long, permanent nerve damage can result.

NATURAL SOURCES OF VITAMIN B12

The most common foods containing vitamin B12 are:
•    Lean beef
•    Liver
•    Clams
•    Fish
•    Poultry
•    Eggs
•    Beans
•    Milk
•    Cheese
•    Yogurt

RECOMMENDED DOSAGE

It is thought that up to 15% of the population has some B12 deficiency.  It is recommended by the National Institutes of Health that adults should not take more than 2.8 micrograms daily, but many medical practitioners recommend doses between 1,000-2,000 micrograms per day–depending on the way the vitamin is taken.  As with any vitamin or substance, different people can safely tolerate different amounts. The amount of Vitamin B12 recommended by a medical practitioner will depend on whether a person is taking other drugs that might create unwanted problems and the person’s diet and lifestyle.

EXCESS VITAMIN B12

Most agree that vitamin B12 has a low level for toxicity in the body in healthy adults.  However, the following have been associated with excess vitamin B12:
•    Chest pain
•    Shortness of breath after mild exertion
•    Swelling
•    Rapid weight gain
•    Pain in the arms
•    Pain in the legs
•    Headaches
•    Dizziness
•    Weakness
•    Fever
•    Rashes