It's a change in material lifestyle. We know from studies, collective experience, and numerous spiritual teachings that happiness doesn't actually come from that form of pleasure, but it remains desirable and hard to change regardless.

(For my part, I've got quite a thing for the noncaloric sweeteners and meat with the evil sodium nitrite. Neither of them have noticeable immediate effects on me, which is how I've changed my habits elsewhere, so I'm kind of stuck on how to progress with them.)