Not sure but I'm guessing it would be because nearly all other minerals or metal minerals can be deficient and cause problems.
I think what is difficult is to interpret cravings. Trying to limit and remove seed oil / pufa I've noticed I don't actually crave those things as much. Like, I'm not eating fried chicken or fried stuff much anymore. I like Chinese but really limit stuff like this and don't crave it so much.
However I ate some good dark chocolate and couldn't get enough of it... I think you may be onto something.