Cobalamin, commonly known as vitamin B12, plays a crucial role in the proper development of blood cells and maintaining healthy nerve tissues. If a deficiency in vitamin B12 is left undiagnosed and untreated, it can result in severe and irreversible damage to nerves and the brain. Pernicious anemia, a condition stemming from insufficient vitamin B12 levels, occurs when patients are unable to produce intrinsic factor (IF) in the stomach, a protein necessary for the absorption of this vitamin. To manage pernicious anemia, vitamin B12 must be administered through injections, as oral intake is ineffective without IF.Pernicious anemia is sometimes referred to as Addison's anemia. Individuals with certain intestinal conditions, such as Crohn's disease affecting the ileum, or those who have had parts of their small intestine surgically removed, may also struggle to absorb vitamin B12. Additionally, strict vegetarians, who avoid animal products, are at risk of developing a B12 deficiency due to the absence of this vitamin in plant-based foods.In the United States, the recommended daily intake of vitamin B12 is as follows: 2 mcg for infants, 3 mcg for children under four, 6 mcg for older children and adults, and 8 mcg for pregnant women. It is advisable for adults to take a daily multivitamin, which is both safe and affordable. Such a multivitamin should contain 400 micrograms of folic acid, around 2-3 mg of vitamin B6, 6-9 micrograms of vitamin B12, and 400 IU of vitamin D. The combination of folic acid and other B vitamins can help reduce homocysteine levels, while vitamin D is essential for preventing certain health issues.Elevated homocysteine levels have been linked to an increased risk of cardiovascular diseases and other health concerns. Most physicians recommend treating homocysteine levels above 9-10 umol/L, with treatment overseen by a doctor experienced in managing coronary heart disease. This treatment typically involves high doses of B vitamins, including 1-5 mg/day of folic acid, 10 mg/day of B6, and 0.4 mg/day of B12.While most vitamin supplements are chemically synthesized in factories, vitamin B12 is unique as it is produced through biosynthesis using bacterial enzymes.
