B12 tongue? How to fix? : r B12_Deficiency Metallic Taste in Mouth: Common Causes Metallic Taste in Mouth and Fatigue: Causes and Treatment Giving Your Cat a Vitamin B12 Boost. The Art of Doing Stuff B12 is one of those vitamins that doesnt get enough credit , At a very basic level, B12 helps your body make healthy red blood cells. Red blood cells are what carry oxygen from your lungs to the Feeling worse after B12 Injection: Answering concerns. La Vie Med Spa