B12 & Metabolism

Vitamin B12 is one of 13 essential nutrients for good health. Like most nutrients, vitamin B12 plays a role in several bodily functions, many related to metabolism. The act of breaking down foods and extracting their nutritional value is a complex web of interconnected chemical reactions. Many of the reactions in which vitamin B12 is involved are precursory steps to the final products of metabolism, whether it be energy production, DNA synthesis or other life processes.

Energy Production

Vitamin B12 functions as a cofactor in chemical reactions involved in metabolism. A cofactor is a chemical compound that is essential for a reaction involving an enzyme to occur. Vitamin B12 functions to ensure that energy production from fats and proteins can take place. A deficiency in vitamin B12 may result in weakness or numbness in legs. A 1999 study by the USDA Human Nutrition Research Center on Aging and Tufts University in Massachusetts estimates that up to 15 percent of adults over 60 may have vitamin B12 deficiencies.

Intermediate Role

Vitamin B12 also serves an essential role in the production of other chemical compounds in the body. Like energy production, vitamin B12 acts as a cofactor for the production of two substances called methionine synthase and L-methylmalonyl-CoA mutase. These chemicals are essential for the formation of over 100 other substances, including DNA, hormones and proteins. It also plays an intermediate role in the metabolism of fats.

Red Blood Cell Formation

In addition to producing other chemicals, vitamin B12 is essential for healthy red blood cell formation. As with the synthesis of other substances in the body, this nutrient helps produce hemoglobin. Hemoglobin transports oxygen to other cells and is a vital component of red blood cells. Oxygen delivery to the cells helps ensure the most efficient way for the body to produce energy, especially when under stress or in fight-or-flight situations. A deficiency in vitamin B12 can result in anemia.

Adequate Intake

Vitamin B12 is a water-soluble vitamin, meaning that excess is excreted. Getting the recommended intake therefore is essential. Unlike other B vitamins, vitamin B12 is found primarily in animal sources, making vegetarians vulnerable to deficiencies. As you age, your body's ability to absorb this nutrient diminishes. The recommended dietary allowance is 2.4 mcg for both adult men and women. Good dietary sources include liver, clams and fortified breakfast cereals. You can also take vitamin B12 as a nutritional supplement or as part of a multivitamin. With proper intake, you can help ensure healthy metabolism.