Vitamin B12 is crucial for the proper development and maintenance of nerve tissues. If a deficiency goes unnoticed and untreated, it can result in severe and irreversible damage to the nerves and brain. A condition, which arises from insufficient vitamin B12 levels in the blood, occurs when patients do not produce the stomach protein necessary for vitamin B12 absorption, known as the intrinsic factor (IF). Individuals with conditions affecting the small intestine, such as Crohn's disease, or those who have had parts of the small intestine removed, may struggle to absorb vitamin B12. Additionally, strict vegetarians who avoid all animal products might experience B12 deficiency due to the absence of this vitamin in plant-based foods. This condition is also referred to as .
