It is one of the capital sins, whose main argument is the exaggerated food intake, motivated by just getting pleasure from it. Like other faults, gluttony is interpreted in various ways; It is often said that it is, basically, dependence on something (drugs, alcohol, sweets), considering this a "bad" fact, since the human being should not glorify entities other than God. Linked to this, some defend the theory that, in reality, all this does not include eating in quantity and enjoying what it provides. Selfishness is said to be one of the causes that give way to sins, as people seek to be on a level similar to that of a powerful religious figure.
The most striking thing, however, lies in the simple fact that food can change in the physical state of a person and that the excess of it can cause the affected person not to help others as they should. As far as possible, the waste of food is also a form of sin, because food, as taught by Christian doctrines, is a gift from God and despising it is a dubious action; something similar is depriving others of the food they need to live comfortably. In the same way, eating luxurious meals when they cannot be paid is also a way of committing mistakes, since it does not allow financial aid to be given to those who may need it or to the church.
Likewise, gluttony is willing for the human being to keep his morals intact, like his body. The imbalance could interfere with your spiritual behavior, so you could not fulfill the assigned tasks in a satisfactory way.