> Intermitted fasting works on the principle that if you eat 1800kcal in one sitting you are going to puke.

Fasting (intermittent and otherwise) causes several physiological responses that have a wide range of health benefits, including reducing risks for cancer and heart disease, and even completely reversing diabetic symptoms for some people. It is absolutely NOT some cheesy self-help way of tricking yourself into eating less because you "just can't fit any more in there" -- you completely made this up.

https://scholar.google.com/scholar?q=fasting