your normal energy drink contains much higher levels of amino acids and vitamins than any food so the actual results on your body are not one hundred percent , and these stimulants can be enhanced by all the caffeine while we do not truly know the full effects . some of the possible side effect of an energy drink are anxiety , insomnia ,  gastrointestinal , muscle twitching , restlessness and periods of inexhaustibly . personally i feel more vigorous testing should should be done for the safety of energy drinkers.