What is the intrinsic factor that allows vitamin b12 to be absorbed?

Question

if someone has perniceous anaemia vit 12 intrinsic factor is missing in body.What is the factor and what must one eat to keep it in the body.What foods would be rich in whatever is required to keep the intrinsic factor sustained?

Answer 1

The factor is called "Gastric Intrinsic Factor". Its a protein produced by the parietal cells of the stomach. It isn't available from foods.

Answer 2

Vitamin B12 deficiencies occur when the body is unable to properly use the vitamin. Pernicious anemia can make the body unable to absorb vitamin B12 from the intestinal tract.

Because vitamin B12 comes primarily from animal products, people who follow a strict vegetarian or vegan diet and do not consume eggs or dairy products may require vitamin B12 supplements. (Non-animal sources of vitamin B12 exist but are highly variable in their B12 content. They are considered unreliable sources of the vitamin.)

Pernicious anemia is the megaloblastic anemia caused by poor vitamin B12 absorption. This can occur when the stomach makes less intrinsic factor, a substance needed for vitamin B12 absorption. This test may also be done to find the cause of nervous system problems.

Those who had surgery on specific parts of the small intestine or stomach are also prone to a deficiency if they do not take B12 supplements.

Low levels of B12 can cause anemia, numbness or tingling in the arms and legs, weakness, and loss of balance.

Vitamin B12 is found in eggs, meat, poultry, shellfish, milk, and milk products.

The Schilling test is used to determine whether the body absorbs vitamin B12 normally.

The vitamin B12 level is a test to tell how much vitamin B12 is in your blood

If you suffer from peptic ulcer, there will be less production of intrinsic factor.

Answer 3

Intrinsic factor is produced by the cells in the stomach. It binds to vitamin B12 and allows it to be absorbed in the small intestine. The unbound vitamin cannot be absorbed from the intestine into the blood stream.

Unfourtunatly we cannot eat or do anything to keep the body producing it.

Some people (particularly elderly people) present with what is thought to be pernicious anaemia but actually just have very low vitamin B12 intake (Vitamin B12 is found in all animal derived products).

The only treatment for pernicious anaemia is a three monthly intra muscular injection of vitamin B12, thus the vitamin is not needed to be absorbed from the intestine.

Answer 4

Bacteria produces vitamin B12

B12 (also called cobalamin due to its central cobalt atom) is a water-soluble vitamin with a very low recommended daily intake requirement, about 2-3 micrograms per day.  That's MICROgrams, not milligrams.  In addition to having extremely low intake requirements, Vitamin B12 is stored in the liver, kidneys, and muscle tissue, and most B12 (65-75%) is reabsorbed by the body instead of excreted.  A deficiency could take from 5 to 20 years of inadequate intake to develop.  The deficiency could be masked by adequate folic acid intake, as the two vitamins work together, but only temporarily.  Eventually a B12 deficiency manifests as nerve damage and pernicious anemia, a very serious type of anemia where red blood cells are improperly formed and white blood cell count is low.

So how could anyone develop pernicious anemia when B12 intake requirements are so low, and when the liver stores so much that it takes years for a deficiency to develop?  The reason touted for the B12 myth is that B12 is found primarily in animal foods.  Very few plant foods provide good sources of B12, they say.  In a way that's true, but only because the source of B12 is not plants OR animals; neither manufacture their own B12.  In the B12 reality, Bacteria are the B12 producers on which both plants and animals rely.  And in humans, that bacteria doesn't necessarily come from plants -- the mouth, upper intestine, and lower intestine all contain bacteria that produce B12.  However, it's unknown if enough B12 to meet the daily requirement comes from internal sources of B12.  More likely, they produce some, and the rest comes in with food and water consumed.

All of the Vitamin B12 in the world ultimately comes from bacteria.  Neither plants nor animals can synthesize it.  But plants can be contaminated with B12 when they come in contact with soil bacteria that produce it.  Animal foods are rich in B12 only because animals eat foods that are contaminated with it or because bacteria living in an animal's intestines make it.