Fasting is a scary thought to some people. Food is deemed important for all kinds of reasons other than raw hunger. What’s that line I keep seeing painted on restaurant walls and on websites: food is love? Fasting means no food, for hours on end (although at least half of the hours are spent asleep).

In the 2002 remake of the movie Swept Away, Madonna’s character talks about the virtues of fasting, and that line is supposed to make you hate fasting, because she’s promoting it, and her character is a snarling, narcissistic plutocrat. But fasting is virtuous, from a symbolic, religious, and ethical standpoint, and there’s even good scientific evidence that a modified form of this practice, called intermittent fasting, is quite healthy.