 [ Symptoms ] can b12 boost metabolism i have just started taking 1000 mcg of vitamin b 12 sublingual tablets i am hoping they will boost my metabolism i am 67 and eating maximum 1200 calories a day dieting regular exercise is almost impossible due to back pain etc does anyone know if the above dosage of b 12 might boost metabolism or am i wasting money and hoping for results that are not likely [ Disease ] hi if its sunny just get out in the sun your get all the b is you need and its all free but no sun block otherwise you wont get non just twenty minutes at a time save you pills till the sun does not shine good luck