I suspect we don't really KNOW much of anything about diet. Once it becomes a matter of conscious attempts to manipulate it we're already in trouble because we are no longer depending on our natural life patterns or natural hunger cues for eating right.
Any of your analyses may be right, or maybe not. I think I am insulin resistant but there are different theories about how to deal with that too. Some say a vegan diet is the cure for instance.
Certainly the fact that modern conveniences have reduced our natural forms of exercise must have a part in all this, and as many of the videos I've been watching suggest, also the fast food industry which aims to stuff as many tasty calories as possible into a small package. These exposes also show that different parts of the food industry have been manipulating the public perception of how we should be eating for over a century by now, with heavy ad campaigns promoting such ideas as that we need more protein, bigger protein-heavy breakfasts that are also heavy on the fat, or milk, or eggs or all the different brands of processed foods touted as "healthy" for all the wrong reasons, or whatever.
All the different diets are trying to deal with the results of these and other influences, and most of them work for weight loss at least to some extent if you stick to them, but I doubt any one of them has the full picture. And they all contradict each other. I don't think we stand a chance of figuring it all out.
Edited by Faith, : No reason given.
Edited by Faith, : No reason given.