Vitamin B12

What is Vitamin B12 and where is it found?

Vitamin B12, also known as cobalamin, is one of eight B-vitamins that is required by the body. The active forms of B12 in the human body are methycobalamin and 5-deoxyadenosylcobalamin. B12 is water soluble, and therefore it not stored in the body and excess amounts are excreted. Vitamin B12 can be found in animal products such as meat, eggs, fish, dairy and some yeast. It is not found in plant foods and therefore vegetarians need to supplement. Some foods are fortified with B12, and it is also available as a supplement and prescription medication. Methylcobalamin is the most functional B12 supplement because the body doesn’t need to convert it since it is in its bioavailable form. Oral supplements are not absorbed well by the body because of intrinsic factor, which is a protein found in the stomach that binds to B12 so it can be absorbed in the small intestine. Some evidence suggests that B12 is better absorbed sublingually. Additionally, doctors prescribe B12 as a prescription medication to those with a deficiency, which can be administered intranasally or as an injection.

What are the benefits?

Vitamin B12 is used for many functions in the body. Vitamin B12 is necessary for the proper function of nerve tissue, brain tissues, and red blood cells. B12 is required for folic acid absorption, and therefore is needed for cell metabolism, since folate is integral in the release of energy. It is also is necessary for metabolism because it is involved in fatty acid synthesis. Vitamin B12 also important for the regulation and synthesis of DNA. It is needed to prevent Vitamin B12 deficiency and pernicious anemia. Additionally, the body needs B12 to convert homocysteine to methionine, stimulate serotonin production, support immune function, and maintain a positive mood.

Are there interactions with food or medications?

Vitamin B12 should not be taken with metformin, proton pump inhibitors and h2 receptor agonists, since it may interfere with their absorption. Vitamin C and Potassium may decrease B12 absorption.

Are there side effects?

Some people may experience diarrhea, swelling or itching, but this is rare.