No, it is not if the body receives all 5 categories of food according to the dietary theory.  Nowadays, the situation changes.  It is very difficult for us to follow the dietary theory.  Contamination and chemicals used in food result badly to the body.  Dietary supplement is then necessary; it helps to prevent deficiency in food essence and assists with detoxification.

However, if somebody gets tiresome, bored with food, he should consider himself whether he sleeps and rests enough, he exercises much enough.  Exercise helps internal systems of the body function better, the body become fresh, gain appetite and become healthier.  If we look after ourselves well, eat suitable food, we can fully make use of energy resulted from food without excess of dietary supplement.