gluttony

i am posting for a friend who asked me for some help. She is trying to help someone close to her loose weight. this person is very heavy and struggles with gluttony. they love food, they have been shared with in the past but still continue to over eat and besides their work are not very active. my friend is fearful for this persons health as well as their spiritual health since they are living in sin by over eating daily. i am hoping to maybe find some teachings or sermons that might be shared with this person.

thanks
rdg