This is due to the fact that many popular vitamin supplements affect the same metabolic pathways that stimulants like caffeine do. Here are a few that could potentially cause unpleasant side effects like anxiety. Even if the B-vitamins are well balanced, as in a B-50 supplement, you still need to be aware that these substances are metabolic stimulants and could take you away from that cherished zen state, particularly if you’re already sensitive to stimulants. Different people react to stimulants differently: Individuals with a COMT mutation (as opposed to a MTHFR mutation) may be particularly sensitive to B vitamins. For most people, this isn’t a supplement you need to take every day unless you have a diagnosed deficiency or are using it therapeutically for chronic fatigue or another condition. If you do take vitamin B12, look for the form methylcobalamin, which is easier to absorb4 than the more common and less expensive form, cyanocobalamin. At the end of the day, all vitamins are metabolic activators so it’s always best to start out with a low dose to see how your body responds.
