After I became fat-adapted, I found it useful to deliberately have a non-keto meal once or twice a month.

I heard some doctors talk about the importance of being metabolically flexible, meaning able to easily flip to burn carbs and right back into ketosis.

For me, when I'm doing really strict keto and fat adapted, and doing intermittent fasting and everything is great.

Then I have a big carby breakfast on a day when I'm going to be extremely active. I get a huge energy boost and don't eat again that day, and next day I've burned through the carbs and am back in ketosis, and back to strict keto.

If I do it more than once or twice a month or if I eat again before I've burned off the carbs, it can start me wobbling, so I don't do it often.

I don't advocate it for anyone else, because we all have to do what works for our bodies, but that works for me.