Of lately I have seen a lot of nutritional drinks in the market, but I donât understand what the use of these drinks is. I mean, one can get all the nutrition by following a proper diet, so why do people spend extra money on energy drinks? Do nutritional drinks have a side effect? How many of you have believed in living on nutritional or protein drinks. My sister takes a lot of it and I feel it would affect her allot later in life. Can anyone out there give me an answer supporting my views?