There is growing evidence that Vitamin B12 is valuable in the prevention of cancer.

Vitamin B12 is produced in the guts of animals, and is found in meat, chicken, eggs and dairy products.  In order to absorb the vitamin B12 from our food, our stomachs must produce hydrochloric acid and intrinsic factor.

Vitamin B12 is necessary for red blood cell and nerve cell and nerve cell formation.  In addition, vitamin B12 is vital for the breakdown of homocysteine, a toxic amino acid.  Measuring homocysteine levels in the blood can be helpful in the detection of a vitamin B12 deficiency.

An example of a vitamin B12 deficiency that has been linked to stomach cancer is with regard to pernicious anemia.  In the case of pernicious anemia, the body attacks its own parietal cells.  This prevents the body from manufacturing intrinsic factor, a protein necessary for the absorption of vitamin B12.  These damaged parietal cells often become cancerous.

New evidence suggests that a vitamin B12 deficiency is a risk factor for other cancers, too, regardless of the cause.  Regarding breast cancer, researchers at John Hopkins University compared blood samples of women with breast cancer to those without cancer.  They found that women with breast cancer had vitamin B12 plasma levels that were lower than those without cancer.

Other cancers that may be linked to a vitamin B12 deficiency include oral cancer, lung cancer and cervical cancer.  One study showed that women with high levels of homocysteine (indicative of a vitamin B12 deficiency) were more prone to cervical cancer than those with normal levels.

Scientists in Alabama tracked women who chewed tobacco for oral cancerous lesions.  They found that women who ate fewer animal products (which contain vitamin B12) were more likely to develop cancerous lesions in the mouth than those who ate more animal food products.

Why is this?  One theory says in order for folate to work properly, it needs the presence of vitamin B12.  The purpose of folate is to help put together the building blocks of DNA.  DNA, in turn, tells the cells when to multiply and divide, and when to stop.  Without vitamin B12, folate is unable to help construct the DNA properly.  This, in turns, leads to uncontrolled cell reproduction, otherwise known as cancer.

One can safely conclude that supplementing your diet with adequate amounts of vitamin B12 will help prevent you from developing cancer.