Stomach cancer kills more people worldwide than any other malignancy except lung cancer, according to a September 2007 article in "Cancer Epidemiology, Biomarkers and Prevention." Stomach cancer and the treatments prescribed for it can affect your ability to absorb nutrients from the foods you eat. If you have stomach cancer and are prescribed B-12, rest assured that there's good reason to take this essential vitamin.
B-12 and Gastric Absorption
Two things can cause B-12 deficiency: failure to consume enough of the nutrient in the foods you eat -- as can occur when following a strict vegan diet -- and failure to absorb nutrients from the foods you eat. Gastric malabsorption can occur due to an number of factors, several of which are linked to stomach cancer. Atrophic gastritis is commonly seen in elderly people. It occurs when the stomach fails to produce enough hydrochloric acid to break down the protein-rich foods that commonly contain B-12. Without enough hydrochloric acid, B-12 remains attached to proteins, and your body cannot properly absorb it. Pernicious anemia, a condition wherein your gastrointestinal system fails to produce an enzyme called intrinsic factor, also prevents adequate absorption of B-12. Both atrophic gastritis and pernicious anemia are linked to increased risk of stomach cancer.
B-12 and Stomach Cancer
A study discussed in the September 2007 article in "Cancer Epidemiology, Biomarkers and Prevention," notes that higher blood levels of B-12 are associated with a lower risk of stomach cancer in patients who show signs of severe chronic atrophic gastritis. B-12 deficiency can also occur due to the treatment methods employed in addressing stomach cancer. Gastrectomy, a surgical procedure in which portions of the gastrointestinal system are removed, can hinder your ability to adequately absorb nutrients, and a B-12 deficiency can result within a year of undergoing the operation, according to a study review published in August 2000 in the "Annals of Surgery."
B-12 Functions
Your body needs B-12 to produce red blood cells, synthesize your genetic code and maintain a healthy nervous system. Without enough B-12, your red blood cells won't be able to transport oxygen to the cells and tissues that need it. B-12 is also involved in the maintenance of the myelin sheath, an insulating layer that speeds up the transmissions of impulses as they travel from one nerve cell to the next.
B-12 Deficiency
B-12 is a water-soluble vitamin, but it differs from all the other water-soluble vitamins in that excess amounts are not completely excreted in your urine. The Merck Manuals Online Medical Library states that your liver stores enough B-12 to last up to 5 years. As a result, it may take a long time before B-12 deficiency starts to impact your health. B-12 deficiency can manifest in symptoms of fatigue, anemia, cognitive dysfunction, balance disorders and tingling in the hands and feet. If you have a B-12 deficiency due to stomach cancer or the therapies associated with it, it is essential that you seek treatment, because prolonged deficiency can cause permanent nerve damage.
References
- Merck Manuals Online Medical Library: Vitamin B12
- Office of Dietary Supplements: Vitamin B12
- PubMed.gov: Enteral Vitamin B12 Supplements Reverse Postgastrectomy B12 Deficiency; Shinya Adachi et al; August 2000
- "Cancer Epidemiology, Biomarkers & Prevention"; The Association of Gastric Cancer Risk with Plasma Folate, Cobalamin, and Methylenetetrahydrofolate Reductase Polymorphisms in the European Prospective Investigation into Cancer and Nutrition; Stein Emil Vollset; November 2007
- Merck Manuals Online Medical Library: Gastritis;
- MedlinePlus: Pernicious Anemia
Member Comments