This is most often confused with actual starvation. It's the time when one thinks one is about to die of hunger, when actually, Americans have no idea what starving is because they are, on average, fed three meals a day.
(1) I'm so starving! I could eat a whole elephant!
(2) Oh really? You are so starving? Because you just ate about an hour ago.
(1) Fine! I'm American Starving.