We all know the craving for certain foods we get, that's because once we've had
those foods our body is telling us there's something in there we're lacking.
If your digestive system is working properly the craving for certain foods
diminishes because you're receiving what you need.
Plenty of extreme examples with pregnant women on craving.
How come I always get a craving for ice cream or chocolate after eating lots of meat?
Yes: cravings comes from the bugs themselves. The really bad carb and sugar cravings need to be starved out. Eating your favorite savory foods really helps you go cold turkey. Smoked salmon and cooked greens really help me do a few days without sugary things.