No, your stomachs digestive system is not designed to exist solely on supplements…..your body needs the living enzymes, naturally occurring sugars, and calories of real food to function properly…..add to that the fact that the industry is not well regulated, and there could be issues with dosage and ingredients not listed on the label….my doctor always told me to eat a balanced diet and take a one-a-day vitamin supplement…..
There are things like complete meal replacement powders which were popularised a few years ago. Also something called the ‘elemental diet’ which people use as an elimination diet for certain ailments. Short answer is yes.