A version of an old joke goes like this: How do you know if someone is Paleo? Don’t worry, they’ll tell you. Not to pick on Paleo eaters; you can easily swap in just about any other diet and the joke works just the same. The enthusiasm some people have for the way they eat can sometimes seem a lot like religious fervor, complete with heartfelt conversion stories and earnest attempts at proselytizing. And that’s no coincidence, argues Alan Levinovitz, a professor of religion at James Madison University and the author of the new book The Gluten Lie: And Other Myths About What You Eat — understanding the way people think about faith goes a long way toward understanding the way people think about food.
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The more Levinovitz looked into it, the more parallels he discovered between religious and dietary beliefs, going as far back as the ancient Chinese texts that are his scholarly specialty. “Two thousand years ago, there were these Daoist monks who decided that if you avoided these five grains — and these were the staple crops of China, what the everyday person subsisted on — you’d live forever, you wouldn’t get any diseases,” Levinovitz said. These monks also came up with intricate recipes for nutritional supplements, which they then distributed with similarly spectacular promises of immortality. “I’m looking at this and I’m thinking, You know, this sounds a lot like the kinds of promises that modern, secular so-called diet gurus make to their followers,” Levinovitz said.