Not the parent but try searching online for fasting and autophagy. There are countless sources regarding this link.

Another good recent study is the intestinal stem cell regenerative boost after a 24 hour fast in mice.

One might say that the links are still not solid, but we do know that lowering glucose levels might be a good idea (hence the interest in metformin) and fasting/keto certainly achieves that without a drug.

I really like the stuff that Mark Sisson writes on fasting[0], because he explains and links all his sources.

0. https://www.marksdailyapple.com/health-benefits-of-intermitt...