In the case of vitamin B12, you could be deficient and not even know it. Here is the start of a four-part article on the nature of vitamin B12 and how it protects us from disease. First up: let’s get to know this essential nutrient.
Vitamin B12 is unique among all the vitamins not only because of its complexity, but also the fact that it contains a metal — cobalt. Hence its technical name, “cobalamin.” It is well established that vitamin B12 is vital for normal healthy red blood cells and nerve cells in our bodies. It’s needed to make genetic material (e.g. DNA) in cells.
In your stomach, hydrochloric acid releases vitamin B12 from protein found in the food you eat. Once released, the vitamin must bind with another protein made in the stomach (the “intrinsic factor”) before it can be absorbed into the body. This might sound a bit complicated, but it’s important to understand, because this is the underlying reason why many people cannot manufacture vitamin B12.
In the U.S., national surveys have shown that most children and adults consume the recommended amounts of vitamin B12. But: a deficiency in vitamin B12 occurs frequently among older adults — more than 20% in fact. A dangerous element is that this is often unrecognized, because of its subtlety, and is not actually treated until serious anemia or dementia has set in.
In a review by France researchers, the common causes of this deficiency include an inability to absorb vitamin B12 (more than 60% of all cases), pernicious anemia (15% to 20%), not getting enough in food, and malabsorption. Of those who can’t specifically absorb vitamin B12 through food, it’s mainly due to a chronic inflammation of the lining of the stomach. This means there is a lack of stomach acid production.
Pernicious anemia occurs in about two percent of people over the age of 60. This autoimmune disease means that the body creates antibodies that progressively destroy the cells lining the stomach. With little or no gastric acid production, there is a lack of intrinsic factor. Thus, you don’t absorb B12. Treatment requires either injections of vitamin B12 or a very high oral dose (1,000 µg a day) of this vitamin.
Other less common causes of deficiency include: surgery in the stomach or part of the small intestine where intrinsic factors are made; celiac disease; tropical sprue (a malabsorption disease); pancreatic insufficiency; a vegetarian diet; alcoholism; long-term use of acid-reducing drugs; and the use of metformin (a drug for diabetes).