DeLauer is not an authority on fasting. He just takes other people’s studies and makes videos on them. I wouldn’t take much of what he says at face value without doing additional research.
There’s no reason to take time off for your metabolism. Your body will be fine. Just keep up with a good diet, your activities and exercises, and get good sleep and work on stress issues.
But taking time off is fine, too, as in it’s your fast, your schedule.
Studies show that fasting does not affect your metabolic rate the way calorie counting does so there’s no need for a break. Check out Dr. Jamanadas or Dr. Fung for these studies that measure metabolic slowdown.
I think a good metric to go by is your performance at the gym or even how you generally feel - if you suddenly feel weaker, probably not a bad idea to eat more and more frequently than you normally would.
It makes sense to me, Thomas also explained once he himself does not actually fast every day, he personally only applies IF 4 out of 7 days, and I think thats not bad.
Because we’re not machines, and fasting is actually a stressor, albeit a mild one.
I think whats better than one week off once every two months is a “most of the time” approach. Like a 60 to 75% out of seven days but not every damn day like a machine because the body will get used to any arrangement really and try its best to keep a nice layer of fat over your mid section because its objective is surviving winter not looking good at the beach.
So yeah sporadic breaks from IF is pretty good imo