Spray glue for the mouth should work wonders!
A piece of duct tape, strategically placed, is also a great weight loss aid. (Care should be taken to leave nasal passages intact.)
With Purim & Pesach coming, along with the great challenges they present to those who may be a bit (…how do I phrase this delicately?… pudgy? rotund? I think I”ll go with–) weighty, I hope attention is given to keeping this thread in the spotlight.