What hinders the absorption of vitamin B12 in the human body?
Consuming meat, fish, eggs, or even dietary supplements is not enough for vitamin B12 to enter the bloodstream; it requires normal stomach acidity, intrinsic factor, and healthy intestines. Eight main factors hinder the absorption of vitamin B12 in the human body, including deficiency of the intestinal protein known as “intrinsic factor,” reduced stomach acidity, prolonged use of heartburn medications and metformin, as well as small intestine diseases and surgeries, strict vegan diets, and exposure to nitrous oxide.
Vitamin B12 is a vital element for blood formation, supporting nervous system functions, and synthesizing DNA in the body, but its absorption process is highly sensitive. According to experts, simply consuming B12-rich foods such as meat, fish, and eggs, or even taking supplements, is insufficient to ensure its entry into the bloodstream; a healthy intestinal environment and normal stomach acidity are required.
The primary obstacle to absorption is the deficiency or absence of “intrinsic factor,” a special protein produced in the stomach that binds to the vitamin and allows the small intestine to absorb it. Its deficiency (as in cases of pernicious anemia) leads to a complete loss of the vitamin. Stomach acidity also plays a crucial role, as reduced acidity makes it difficult to break down the vitamin from dietary proteins, a situation that often occurs with long-term use of acid-reducing medications and heartburn treatments. Furthermore, long-term use of diabetes medications impedes intestinal absorption of the vitamin, necessitating regular monitoring of its levels.
In this context, small intestine diseases such as Crohn’s disease, or any inflammation and damage to the ileum, negatively affect absorption efficiency. The problem worsens after gastric surgeries or removal of parts of the intestine. On the other hand, strict vegan diets emerge as a cause of vitamin deficiency due to the absence of animal sources and fortified alternatives. Finally, repeated exposure to nitrous oxide gas can inhibit the vitamin’s vital functions in the body. Conversely, doctors emphasize that common beverages such as tea and coffee have no negative impact on levels of this essential vitamin.
Source: health.mail.ru
