I like the Snickers commercials. The premise is that you’re not yourself when you’re hungry. You behave like a totally different person and you have no idea why. Then you get food and realize: oh! I was just hungry!
When I was a kid I remember every time I would get upset about something my family would exchange glances and ask one another when was the last time I ate. I have learned to spot my signs of hunger. Irritability, mental confusion, shakiness are all symptoms that prompt me to check my stomach and consider whether or not I might need food.