Vitamin B12 is one of the eight B vitamins, and is important for brain function and the formation of blood. B12 deficiency can cause many diseases. Deficiency can be treated by diet or by B12 injections. Since B12 is hard to assimilate through the stomach, sublingual B12 is advised. B12 is water-soluble, is made up of a complicated chemical structure, and contains the element cobalt. The type of B12 used in food supplements is called cyanocobalamin.

Brain scans can now measure brain volume and a study of patients deficient in vitamin B12 showed their brain volume at half of those with high blood levels of vitamin B12. It is an important component of the nervous system and for DNA synthesis. Without B12, the body can't manufacture blood and leads to anemia. Vitamin B12 is also responsible for maintenance of memory. Deficiency of B12 causes fatigue, diarrhea, memory loss, anemia and poor nerve function.

Another function of B12 is that it lowers the blood level of homocysteine. Homocysteine is a naturally occurring amino acid in protein, but without enough B12 in the blood, homocysteine creates inflammation. Homocysteine is now considered a more important marker for heart disease and stroke than cholesterol. Since heart disease and stroke are the main causes of death of many Americans reducing homocysteine in the blood is important and B12 is one of the important nutrients that does so.

Research has also shown that homocysteine can also prevent migraines and age-related macular degeneration. Headache pain and severity were both reduced when homocysteine levels were brought down by B12 and folic acid supplementation. Age-related macular degeneration risk increased four-fold in those with lowered levels of B12 (under 125 pmol/L). Over 2000 participants were studied via photographs of their retinas.

B12 is contained in many meats and fish. It is hard for vegetarians to get enough B12 because most of the sources are of animal origin. The best source of B12 is clams and other mollusks. There is nearly 85 mcg of B12 in just 3 ounces of clams. The next best source is liver, with 47 mcg in a slice. Salmon and trout have 5 mcg in three ounces.

Recommended dosage of B12 is 500 mcg a day. The supplement is inexpensive but difficult to absorb through the digestive system. So look for sublingual (under the tongue) forms, those that are sealed to prevent destruction in the gut, or get a B12 injection. Be sure to get enough vitamin B12 to fuel your brain, your blood, and your heart.

Additional Information

Vitamin B 12

Dietary Supplement Fact Sheet: Vitamin B12

Mayo Clinic: Vitamin B12

About the author

Melanie Grimes is a writer, screenwriter, journal editor, and adjunct faculty member at Bastyr University.She has written an eBook on natural treatments for the flu, available at her blog.A trained homeopath, she also raises alpacas and is an avid spinner. She is the editor of the homeopathic journal, Simillimum, has been a medical editor for 15 years, won awards as a screenwriter, taught creative writing, founded the first Birkenstock store in the USA and authored medical textbooks.