Now, if ever there was blatant advertising...........Bet you can't eat four and still get airborne.
The thing to remember with dieting, is that you don't need anywhere near as much food as you normally eat...well, at least those of us that are lucky enough to live in the ‘Developed World'.
Almost no one that I have ever met, only eats what they need. The one exception is a vegetarian physiotherapist neighbor and friend. He would come home from a long day and eat a plate of stuff that I would have taken to be left-overs from my vegetarian wife's plate: a lettuce leaf and a couple of grapes seemed to fill his minute platter. He is now in his late 80s, fit, and sharp as a razor.
Our flying lifestyle makes eating for comfort, something of a necessity, but it needn't be.
Training the stomach down to size is the start, and then never ever stretching it again. This is how a multi-thousand $ operations works, why go through that? Let it get small naturally, and then keep it that way. It does take a period of depravation, and be carful if you are actively flying, but it will work. Plenty of water is one of the tricks.
I'm a fine one to talk, yo-yo dieting for the last fifty years.