True! A fairly well fitting, inelastic waist line will rapidly inform you of any overindulgence. The key is to then modify your eating and exercise habits until the situation is resolved, rather than exchanging your pants. :D

> It works so well that I wear sweats.

Hahahaha yep sometimes during the holiday season.

> A fairly well fitting, inelastic waist line will rapidly inform you of any overindulgence.

This works well: https://www.varusteleka.com/en/product/nva-leather-belt-blac... . (Out of stock, though. The nearest equivalent may be the Bundeswehr model.)