Well… Is not a caveman theory… Is actually kind of a new topic in nutrition…
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9036397/
This paper even address the first law of thermodymics, which you really do not seem to understad. Bodies do not use 100% of the energy in your food, the usaged percentage is variable and what is not use you just shit, conserving the 1st law.
And true, people go back to eat too much, but you can’t assure that 100% of the cases of weight regain after diet are coused because of that, there are:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6082688/
This is quite the hot topics between nutrition experts, but I’m guessing you already know that, since your seem to belive to already have analysed all possible information about this ultra-complex topic.
Yes, CICO works most of the time if you count well enough, but there are somw cases where your hormones will just fuck you over.
I really can’t tell if you’re trolling or if you reaaaaaaallyyyyy think you know what the 1st law actually means but are not capable enough to see that open systems are not bound by it in the way you think they are.
https://bookdown.org/asvn90/Understanding-Thermodynamics/the-first-law-for-open-systems.html
Take a look at chapter 5.2, it explains how the 1st law applies to open systems -like your body, in case you don’t get why I am talking about open systems-
In shot
Food = energy + shit (+others)
You can shit more or less, depending on how your body process food. I hope that one is simple enough for you.
Also: maybe is easier to understand https://www.youtube.com/watch?v=lPrjP4A_X4s
Is Pihole not the simpler way, since it configures Unbound for you?