Personally, knowing my body, it's more like it wants to be healthier, and it's unwilling to tolerate me making poor choices for it. The body has entrusted its health to me, and now that I've been making better choices for it, it's gonna remind me more actively when I choose something suboptimum.
Kinda like "OK, Stupid, you've been at the controls long enough. You think I like having to clean up after the crap you put in here? Well, let's see how you like THIS!"
There's nothing quite like self-inflicted, massive, internal pain to motivate behavioral changes.