The Vitamin B12 Blood Test from Walk-In Lab helps diagnose macrocytic anemia and neuropathy, and evaluates and monitors treatment for Vitamin B12 deficiency.Patients will be provided fasting instructions upon ordering the Vitamin B12 Blood Test. Results will be available in 1-2 days. Insurance and a doctor’s order are not required to purchase this test.Vitamin B12 is necessary for the formation of normal red blood cells, nerve function, and tissue and cellular repair. It is not produced in the human body, but rather ingested when consuming foods such as red meat, poultry, fish, milk, eggs and fortified products such as certain breakfast cereals and breads. Deficiencies can be caused by malabsorption (when a disease or other condition interferes with the absorption process) or insufficient dietary intake, although this is unusual in the United States due to the number of food items that have addedB12.Vegans and those who do not consume animal products may bemorepronetodeficiencies.A deficiency can lead to macrocytic anemia (when the body produces fewer, but larger red blood cells) and neuropathy (nerve damage causing tingling and numbness in the hands and feet). Symptoms that suggest a Vitamin B12 deficiency include dizziness, weakness, fatigue, and/or a sore mouth or tongue, although these could be caused by other conditions as well. A Vitamin B12 Blood Test may be ordered if a CBC with Differential detects large red blood cells.