Use

Vitamin B12 plays a crucial role in red blood cell formation, neurological function, and DNA synthesis, and its deficiency can lead to fatigue, cognitive impairment, and even anemia. Since B12 is also essential for energy metabolism and neurotransmitter production, maintaining optimal levels can enhance mental clarity, mood stability, and overall vitality. Regular testing is particularly useful for individuals at risk of deficiency, such as vegetarians, older adults, and those with gastrointestinal conditions that impair absorption.

From a hormone optimization perspective, B12 supports adrenal function, thyroid health, and proper methylation—critical processes in hormone regulation. Deficiencies can contribute to imbalances, including low energy, poor stress adaptation, and disruptions in sex hormone production.

Vitamin B₁₂, or cyanocobalamin, is obtained exclusively from animal dietary sources, such as meat, eggs, and milk. Vitamin B₁₂ requires intrinsic factor, a protein secreted by the parietal cells in the gastric mucosa, for absorption. Vitamin B₁₂ and intrinsic factor form a complex that attaches to receptors in the ileal mucosa, where proteins known as transcobalamins transport the vitamin B₁₂ from the mucosal cells to the blood and tissue. Most vitamin B₁₂ is stored in the liver as well as in the bone marrow and other tissues.

Vitamin B₁₂ and folate are critical to normal DNA synthesis, which in turn affects erythrocyte maturation. Vitamin B₁₂ is also necessary for myelin sheath formation and maintenance.of nerves.  The body uses its B₁₂ stores very economically, reabsorbing vitamin B₁₂ from the ileum and returning it to the liver so that very little is excreted.

Clinical and laboratory findings for B₁₂ deficiency include neurological abnormalities, decreased serum B₁₂ levels, and increased excretion of methylmalonic acid. The impaired synthesis associated with vitamin B₁₂ deficiency causes macrocytic anemias. These anemias are characterized by abnormal maturation of erythrocyte precursors in the bone marrow, which results in the presence of megaloblasts and in decreased erythrocyte survival.

Pernicious anemia is a macrocytic anemia caused by vitamin B₁₂ deficiency that is due to lack of intrinsic factor. Low vitamin B₁₂ intake, gastrectomy, diseases of the small intestine, malabsorption, and transcobalamin deficiency can also cause vitamin B₁₂ deficiency.

Pregnant women need increased amounts of folate for proper fetal development. If a woman has a folate deficiency prior to pregnancy, it will be intensified during gestation and may lead to premature birth and neural tube birth defects, such as spina bifida, in the child.

Preparation

Fasting sample preferred. Do not take any supplemental B12 doses the day of testing.