I have noticed the same thing as some of the other posters. If I'm truly hungry, I'm willing to eat (healthy) anything. Salad, fruit, ...no dressing? Whatever, I'm hungry and I'll take it. However if I find myself saying I really don't want a salad..then I know I'm not as hunger as I think.
Did you ever go out to the kitchen because you were "hungry" and nothing looked or sounded good to the point you leave the kitchen b/c there's nothing you want? When I've done that, I was not hungry, just bored!