"I have occasionally had symptoms related to being hungry, like dizziness and irritability which go away when I eat."
That's more or less what I'm talking about. Dizziness, lack of energy, difficulty thinking, then I eat and it's dealt with. If I eat more, it's dealt with for a longer amount of time.
I call that my need for food - I call it my hunger. I don't know a better name for it. But the less of it that happens, the less food I need to eat to get rid of the feeling.
I'm eating roughly 2600-2800 calories a day. If I eat less, I suffer (unless it's one of those days where I'm not as needy for food).