I played around with intermittent fasting in the early stages of covid lockdown because I was gaining weight being inside all the time.

I would frequently be in ketosis before breaking fast per the urine strips - despite not intentionally limiting carbs at all.

It was an interesting experiment but after having a kid I found it tough to keep the routine. I was in amazing shape for a little while though

When adhering to if+keto well lines up with a period where social pressures don't compel me to eat, it's not terribly hard to go 2 or 3 days without eating just by not eating until I feel hungry.