Your daily habits contribute as much as one-third to your risk for certain types of cancer, according to the American Cancer Society. Stay physically active, reach and maintain your ideal weight and eat a nutritious and well-balanced diet to decrease your cancer risk. Scientific research has shown that deficiency of some vitamins, including vitamin B-12, influences risk for particular types of cancer.
Vitamin B-12 Functions
Vitamin B-12, a member of the B-complex family of water-soluble vitamins, serves a number of important health functions. Vitamin B-12 maintains proper nerve function, is involved in production of DNA, blood cell formation and production of amino acids -- the building blocks of protein. Deficiency of vitamin B-12 can result in blood conditions, such as anemia, neurological disorders and increased risk for cardiovascular disease. Food sources of vitamin B-12 include meat and dairy products. Vitamin B-12 is lacking in plant foods, making it a challenge for strict vegetarians to obtain sufficient quantities.
A study of breast cancer in more than 700 women, published in the March 2011 issue of the "American Journal of Epidemiology," found no association between B vitamin intake and breast cancer in postmenopausal women. However, among women in a Mexican study published in the March 2006 issue of "Cancer Epidemiology, Biomarkers and Prevention," higher dietary intakes of vitamin B-12 and folate -- another B-complex vitamin -- were associated with lower breast cancer risk. The protective effect of high vitamin B-12 levels was stronger than the risk associated with low levels in this study.
Researchers at the Cancer Research Center of the University of Hawaii found that cervical cancer may be prevented with vitamin B-12. The study, published in the November 2003 issue of the journal "Cancer Causes and Control," found that vitamin B-12 supplementation, along with high dietary intakes of the B-complex vitamins riboflavin, thiamin and folate, conferred a protective effect that reduced cervical cancer risk. Additionally, researchers observed that the lowest nutrient intake occurred in women who smoked or drank alcohol, habits that can deplete some vitamin levels.
A long-term study published in the 2001 issue of the "American Journal of Epidemiology," evaluated three B-complex vitamins: B-12, B-6 and folate. The researchers did not find an association between vitamin B-12 levels in 300 lung cancer patients. However, a protective association between high vitamin B-6 levels and lower lung cancer risk emerged in the study.