Author actually frames the situation as more dire level of hunger then just "dinner was late by two hours" kind of hunger. The state of euphoria he describes when he could steal some basic food suggest hunger was quite serious. Not eating enough is actual health hazard, especially in the puberty even if you are not in the "loosing muscle, brain matter and veins material due to body eating itself" starving level.

Second, I am comparing it to the baseline in article - eating peanut butter, beans and hot dog sausage. I am not saying it will instantly kill you.