Of course, much more research is necessary to demonstrate a clear link between the two, but intermittent fasting is a great tool nonetheless (see more of its benefits here). But there’s more than a few time restricted eating plans out there—how long do you need to fast to reap those autophagy-related benefits?
Here’s what Fung suggests: “I think in order to get into autophagy, you have to be up into the 16-plus hour range.” You may need more or less, depending on your exact eating habits and weight, but a 16-hour fast is what he generally recommends.
However, Fung also encourages an occasional longer fast, if you can handle it. “I think it’s always beneficial once in a while to get into a longer state, which is sort of 24 hours plus because then, you’re really gonna activate [autophagy],” he says. “You can store sugar in the form of glycogen in your liver, and that will last about 24 hours. [After 24 hours], you can start to break down some of these other proteins you don’t need.”
That’s not to say you have to complete a super-long fast (shorter 16-hour fasts are A-OK), but Fung says you may experience greater autophagy if you do it occasionally—think once or twice a year.