When considering gluttony and hanging our heads in shame (we all indulge at times) we need to remember that there is virtue to help us fight the temptation. Temperance blesses us with a level-mindedness and restraint to resist what is more than is necessary.
Temperance helps us to judge between what is wanted and what is needed. It also helps us to see past our own self-interests to public interests, helping us to recognize the wants and needs of others beyond our own. Temperance also embraces the importance of self-control and delayed gratification.
But how does this help with gluttony?
By keeping in mind that God has given you exactly what you need, there is no need to seek out even more for ourselves. Be content with what we have been blessed with. Temperance also blesses you the self-control to ensure that each day is held in its proper balance, giving God and our loved ones their due time in our lives. We practice temperance each time we recognize that as much as we want the new sweater, our money has a more important role to play. Temperance is used each time we are giving of our time and ourselves, sharing what we have with those around us. If gluttony is a sin of self-indulgence, then temperance is a grace of selfless mindfulness.
Temperance extends beyond that particular sin of gluttony. Even though it is little-discussed or praised virtue, temperance is necessary to help the other virtues take root in our lives. The self-control and intentional-ness that comes with this virtue helps us to take necessary steps towards being a more virtuous, spiritual person.