Justina Ragauskaitė<sup>1

1</sup>Lithuanian University of Health Sciences, Academy of Medicine, Kaunas, Lithuania

Abstract

           Vitamin B₁₂ deficiency is a common health problem worldwide. Although the real prevalence of vitamin deficiency in the general population is not known, but it is observed that the incidence increases with age. Vitamin B₁₂ is essential for the normal neurological function of the human body, as well as the production of red blood cells and DNA synthesis. Lack of this vitamin can lead to anemia syndrome, which is characterized by two main symptoms: megaloblastic anemia and / or neuropathy. The causes of vitamin B₁₂ deficiency can be various, including congenital disorders of cobalamin metabolism, absorption, old age. However, the intestinal flora of humans can synthesize vitamin B₁₂, but it cannot absorb it, thus, the vitamin must be obtained with food. The highest level of vitamin B₁₂ are most found in animal liver, red meat, milk and fish. Daily consumption of these foods help people reach the recommended daily rate of vitamin B₁₂ (3.0 µg per day). Diagnosis of vitamin B₁₂ deficiency usually involves a general blood test, serum determination of vitamin B₁₂, methylmalonic acid (MMA), homocysteine and holotranscobalamin (holoTC). Vitamin B₁₂ deficiency is the most common vitamin deficiency that requires clinical treatment. Hypovitaminosis of vitamin B₁₂ can be treated by intramuscular injection of cyanocobalamin, hydroxocobalamin or by oral vitamin B₁₂. There are also many forms of vitamin B₁₂ supplements that are widely available and effective for most people. In this article, we will review vitamin B₁₂ sources, metabolism in the body, diagnostic and treatment of vitamin deficiency.

Keywords: Vitamin B₁₂, deficiency, metabolism, treatment.