Vitamin B12 is one of the eight vitamins that make up the B-complex. It is also known as cobalamin because it contains high levels of the metal ion cobalt. Like all B-vitamins, B12 is water-soluble. However, B12 differs from the other B-vitamins as it can be stored in the liver and kidneys for years.
Vitamin B12 works together with folic acid in the body to keep blood and nerve cells healthy and to synthesize and regulate DNA. Within the nervous system, vitamin B12 ensures healthy myelin sheaths, the fat-like coverings that surround nerve cells and help them receive and transmit signals.
Like all B-vitamins, cobalamin plays a role in energy production by working with enzymes to help metabolize carbohydrates, fats and proteins. Due to its role in energy metabolism, B12 is often used as a way to increase energy or endurance.
A special digestive secretion called intrinsic factor is required for the body to break down and absorb vitamin B12 in the small intestine. As a result, in conditions that involve intestinal disorders or malabsorption problems (e.g., celiac disease), a deficiency in B12 can occur. Vitamin B6 and folic acid are also important for vitamin B12 absorption. A high intake of folic acid can mask a vitamin B12 deficiency which if left undetected can cause neurological damage.
Cobalamin supplementation is used in treating conditions such as fatigue and Alzheimer’s disease, and to lower blood homocysteine levels. A high level of homocysteine in the blood is an independent risk factor for both Alzheimer’s and cardiovascular disease. However, at this time, there is no clear evidence that lowering homocysteine levels reduces the risk of developing either disease, and further study is needed.
Vital to produce healthy nerve and red blood cells
Enhances neural transmissions throughout the body
Helps with metabolism and energy production
Regulates proper DNA synthesis
No plant or animal can produce vitamin B12. Only bacteria, yeasts, molds and algae can manufacture this vitamin.
The B12 content of plants depends on their relationship to the environment. In plants that provide some B12, it is the microorganisms in the soil (bacteria, yeasts, molds, fungi) or roots that determine the amount of this nutrient in the plant food. Depending on these conditions, cultured and fermented bean products (tofu, miso, tamari), sea vegetables (kelp), algaes (blue-green algae) and yeasts (Brewer’s yeast) may contain significant sources of B12.
The B12 content of animals depends on their ability to store the vitamin. Given that B12 is stored in the liver and kidneys, it comes as no surprise that these animal products are the richest sources of this vitamin. Other good sources include eggs, meat, dairy, clams and fish like sardines and salmon.
Certain food products are fortified with B12 like breakfast cereals and so