The late Dan Duchaine that on a cyclical ketogenic diet, 5 days on and 2 off, you should take a full 10 days off every 6 weeks. Or at least until your morning basal temp. comes back up to normal, which is generally 10 days. However, if you use an ECA stack or some kind of fat burner I'm sure it could be extended. I usually do w/ fat burners 6 or 7 weeks on, otherwise the fat loss does seem to diminish. Currently I am taking 10 days off of dieting anyway, just be sure not to overeat. Because you are definitely in a position to gain some fat back, other than the usual water weight. In fact, I'm certain that I will probably gain a pound or two of fat, but that simply can't be avoided when your metabolism is down. Usually though I'm back to the weight I was by the end of week 1 of dieting again, always by the second week if not lower.