Vitamin B12 is an essential nutrient that plays a key role in keeping your nervous system healthy, helping your body produce red blood cells, and supporting DNA synthesis. When you have a B12 deficiency, it can lead to a range of health issues, from mild fatigue to more serious complications. Vitamin B12, also known as cobalamin, is a water-soluble vitamin that is naturally found in animal products, such as meat, fish, eggs, and dairy. It’s important for nerve function, red blood cell production, DNA synthesis. Your body needs B12 to perform a number of critical functions including energy production, neurological health, mood regulation. B12 deficiency can occur for several reasons: dietary deficiency (vegetarian/vegan), absorption issues (pernicious anemia, Celiac disease, Crohn's disease, GI surgery), older age, certain medications (proton pump inhibitors, metformin). If you are deficient in B12 you may experience variety of symptoms such as fatigue, pale or jaundiced skin, numbness/tingling, balance problems, memory issues, mood changes, glossitis. If you are experiencing any of these symptoms its important to see your doctor to have your B12 level checked. Once you are diagnosed, your doctor may recommend supplements which are typically oral or sublingual (under the tongue). For people with severe deficiency or GI absorption issues B12 injections maybe recommended. They are typically prescribed by your doctor to be self-administered or given in clinic. Its also available as an intranasal spray. For older adults deficiency may lead to increased risk of dementia or neuropathy.