Another part of u/ex150's ex150 diet that strikes me as possibly spurious is that he only eats proper food (the sort that isn't whipped cream) once a day. And it's always the same, beef and some green veg.
That sounds like it takes some willpower, and although I have iron willpower if I need it, using willpower to lose weight sounds like a terrible idea.
I want to listen to my body and its needs, and satisfy them as and when they need satisfying.
So, the potentially load-bearing parts of ex150 seem to me to be:
(a) no-PUFAs
(b) very little carbohydrate, and that starchy rather than sugary
(c) restricted, but adequate protein
(d) all other necessary calories from dairy fat
So my compromise ex150ish diet will be:
A pot of everlasting stew, containing:
1kg 80/20 ground beef per week
with as much in the way of chopped tomatoes, passata, tomato puree, and not-terribly-carby vegetables either fresh or tinned as desired/convenient
plus all types of spices and sauces and salt and butter and maybe coconut oil, added to stew as desired to make it taste good.
(but not anything containing sulphites or significant carbs, so for this purpose potatoes and yams don't count as vegetables, and certain sauces such as HP are out.)
And apart from that, since there's not going to be much in the way of calories in that:
double cream
eat either as desired, no routine
To be honest, that's not *very* different from what I routinely cook for myself, plus eating a lot more double cream than seems entirely sane.
The main change will be avoiding bread, yams, and potatoes, all of which I love, but none of which are particularly nutrient filled. And replacing the “empty” carbs they contain with “empty” fats from double cream.
The other big change will be dropping my favourite breakfast of yoghurt, muesli, fruit and honey/maple syrup. Breakfast will be double cream straight out of the pot.
And also cheese. I like cheese, but it’s got some protein in it, and the protein restriction may be part of what makes ex150 work for u/ex150.
That doesn't sound too unpleasant, although I will miss my greek breakfast. Time will tell.
Because I'm a bit worried that I might be inadvertently cutting out essential micronutrients, also one Sainsbury's A-Z vitamin and mineral pill every day:
https://www.sainsburys.co.uk/gol-ui/product/all-vitamins--minerals---supplements/sainsburys-a-z-multivitamins---minerals-x-60
He may chime in to speak for himself, but many folks with binge-eating tendencies find OMAD to require less willpower -- something about beginning to eat triggers a desire to eat a ton, but this (in his case) can be crushed with enough heavy cream.
While you're thinking about multivitamins and how we've all been lied to about health, consider that the single-pill multivitamin was a marketing decision. Something like Animal Pak (sic) is a whole fistful of pills for roughly 1 USD per day. Something like Athletic Greens is twice that, and might be twice as good.
For me, the one meal actually doesn't take any willpower. It's basically what I was eating every day for the last few years on keto before starting ex150 - I just reduced the portion size a lot. I just have very simple tastes, but this is the most delicious meal I can think of and I eat it every day. That might not be true for everyone else, but your stew might be the most delicious meal for you! And then it won't take any willpower/discipline.
Also I think you pretty much summed up ex150 quite well and got all the load-bearing parts (I can think of) right.