Your body naturally tries to maintain homeostasis. When you cut your food supply below what your average is, and probably has been for years, your body will fight you in every way it can.

For example, I eat too much and started eating less. I now eat normal portions instead of portions fit for 2 people. I have more than enough food and energy, and yet, I am hungry. The hunger is fake, I certainly don’t need more calories. But my body thinks it does based off of its knowledge.