Vitamin B12 is found in animal foods. Normally, vitamin B12 is easily absorbed in the last part of the small intestine (ileum) leading to the large intestine. However, in order to be absorbed, the vitamin must combine with intrinsic factor, a protein produced in the stomach.
Who Takes Vitamin B12?
The body absorbs vitamin B12 from food in two stages. First, hydrochloric acid in the stomach separates vitamin B12 from the protein it is bound to. Second, the released vitamin B12 then combines with a protein produced by the stomach called intrinsic factor, and the body absorbs them together. seven
How do we absorb vitamin B12?
Vitamin B12 is linked to a protein in your stomach called intrinsic factor. This mixture of vitamin B12 and intrinsic factor is then absorbed by the body in a part of the intestine called the distal ileum.
What Blocks B12 Absorption?
The most common cause of vitamin B12 deficiency is insufficient intake. The following conditions can lead to insufficient absorption: Bacterial overgrowth in part of the small intestine. Impaired absorption (malabsorption disorders such as celiac disease or certain diseases of the pancreas)
What affects B12 absorption?
Atrophic gastritis, in which the stomach lining has become thinner. Pernicious anemia, which makes it difficult for your body to absorb vitamin B12. Conditions affecting your small intestine, such as Crohn’s disease, celiac disease, bacterial growth, or a parasite. 3
How is B12 best absorbed?
In the stomach, hydrochloric acid and enzymes break down vitamin B12 in its free form. From there, vitamin B12 binds to a protein called intrinsic factor so it can be absorbed further down the small intestine. Dietary supplements and fortified foods contain vitamin B12 in a free form, making it easier to absorb.
Does the body absorb vitamin B12 supplements?
Your body cannot absorb all of the vitamin B12 from supplements. Absorption is limited by the amount of intrinsic factor produced by your stomach. Intrinsic factor is required for your body to absorb vitamin B12. For example, only about 10 µg of a 500 µg oral supplement is actually absorbed by healthy people.
Can vitamin B12 be absorbed without intrinsic factor?
A small amount of vitamin B12 is absorbed by passive diffusion without intrinsic factor. 1