Vitamin B12

Let’s talk about vitamin B12. As opposed to all the other B vitamins, which you must have daily in your diet, the body can store supply of B12 for up to two years in the liver. B12 is needed in the production of red blood cells, the maintenance of the central nervous system, the metabolism of fat, protein and carbohydrate. The absorption of B12 requires the production of adequate stomach acid and an intrinsic factor. An intrinsic factor is secreted in the stomach and is a substance that unlocks B12 from food. Gastric bypass, used for the management of obesity, reduces the amount of acid and intrinsic factor that the stomach produces. This loss also occurs naturally with the aging process and about 30% of those over 50 years old can mal-absorb the vitamin.

B12 vitamin deficiencies can take years to develop. If someone goes to the doctor after gastric bypass they may find they have adequate amounts of B12 in their blood. Over of time, however, they may lose the ability to absorb this vitamin. Sometimes they use injections or big oral doses of 500 milligrams. The injection only works if you actually have deficiency. You may see a lot of people believing that they need to have a B12 injection every month. That is true if you’re deficient.

B12 deficiency can cause a type of anemia called Pernicious anemia. You can also have nerve destruction that’s irreversible. Make sure you have adequate amounts, and if you are over the age of 50 or just had a gastric bypass, you should check your status. Vitamin B12 is only found in animal sources. If you’re vegan and don’t consume any food from animal sources, you may want to consult your doctor about whether you need a supplement or not.

Recent research also suggests that a deficiency of B12 may also increase the likelihood of neural tube defects.

There are no toxicities associated with B12.

Daily Requirements

Adults: 2.4 micrograms.

Foods Rich in Vitamin B12

113 grams calf's liver, braised	41 micrograms
113 grams beef tenderloin, broiled	2.92 micrograms
1 cup cow's milk, 2% fat	0.9 micrograms
1 egg, boiled	0.49 micrograms
1 cup yogurt, low-fat	1.38 micrograms