B12 tongue? How to fix? : r B12_Deficiency Weird Taste in Your Mouth? These Infections Are Often to Blame Why can I taste saline and medications when they're inserted into my IV? Office for Science and Society McGill University 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 Vitamin B12 deficiency symptoms: A metallic taste in your mouth could be a sign Express.co.uk