Why Fasting Works
Ancient Romans were onto something
Ancient Romans found the idea of breakfast repellent. They were “obsessed with digestion,” according to the historian Caroline Yeldham, and believed eating more than one meal a day was unhealthy and gluttonous.
If that’s the case, the likes of Cicero and Marcus Aurelius were early adherents of “intermittent fasting,” which is a catchall term for a handful of related diets that either restrict food intake to certain hours of the day or limit intake several days each week. The nomenclature can get confusing, but the most popular and evidence-backed of these fasting plans are known as time-restricted feeding, alternate-day fasting, and the 5:2 diet.
The first — time-restricted feeding — involves compressing the day’s snacks and meals into a narrow window of time, usually six or eight hours. The operating theory here — one that, to an extent, nearly all nutrition experts support — is that the human body wasn’t designed to consume and digest food all day, every day.
“Most people are putting something caloric in their mouths essentially every minute they’re up, and we know that from an evolutionary perspective, this is not how humans or animals are geared to eat,” said Mark Mattson, a fasting researcher with the National Institutes of Health and an adjunct professor of neuroscience at…
