If there's any mental effect, it's most likely from eating less food (and most likely healthier food) and feeling better because of that.
It doesn't increase your appetite for healthy food. It will punish you for eating bad food. "Don't eat that steak, you're going to have crazy stomach pain tomorrow if you do!"
It doesn't increase your appetite for healthy food. It will punish you for eating bad food. "Don't eat that steak, you're going to have crazy stomach pain tomorrow if you do!"