You don't seem to be disagreeing with anything I wrote, but just a comment on your last paragraph:
> Going back, what's common sense is to eat natural foods rather than avoid them. Processed stuff is the real danger, including meal replacement with powders.
I think avoiding something "processed" is a terribly blunt tool, which will likely end up not serving you. What does processed even mean? I usually buy pre-washed potatoes because I'm lazy, those are processed. As is my cheese, as is my chili sauce, my peeled nuts, and most if not all my spices.
I don't think we're there yet with Soylent and similar meal replacements, but I don't doubt that we in the future will have meal replacements with much better macros, better taste and fun texture, as well as lab grown meats and meat substitutes that taste better.
Processed doesn't mean inherently bad, and there's nothing definitive saying that processed through photosynthesis is better than on a molecular level processed through a series of tubes in the other kind of plant. The only thing making "processed" foods bad are businesses cutting corners on cost with the only goal of delivering something palatable, not something healthy. That isn't a process problem, but a market problem.
Apologies for replying to the wrong parent, though!
The issue with processing in your example is mainly the corn syrup and coloring (if not using natural coloring like carotene etc), as well as to a lesser extent shredding of the corn or wheat which leads to a higher glycemic index.
But as we've made cheese puffs out of corn and varying degrees of terrible chemicals, we now have chips made from quinoa, beans, lentils etc, which I'm not saying are great, but better.
If I could have a snickers with 0 calories and no carcinogens, or pringles made out of broccoli, you can bet your ass I would pop that package without stopping.
So again, even with our agreed definition of processed, it might in 95% of cases right now mean "bad food", but it doesn't have to.
Fine, it doesn't have to. And if we have the technology to send someone's car into space, we can surely create something processed and perfect in terms of glycemic index, macronutrient balance, and so forth. But as a general rule, almost all that stuff has flaws. For example, even the organic quinoa chips (and puffs which I'm very guilty of inhaling a bagfull of) has a lot more sodium than you really need.
That and I'd argue, in the case of certain concentrated items like whey protein chips, it's kind of unclear what side effects we might discover one day (as we did with refined sugars and obesity and diabetes and such). That said, I'm risking it.
Lest I be accused of hypocrisy for occasionally eating the healthy processed stuff you describe, I'd argue that for the general (ignorant, at least in the US) public, 'avoid processed' is a good rule of thumb.
But there are many things involved here, for instance, if you don't eat any fat or protein, you will die, however, if you don't eat any carbohydrates, then you won't die, is this common sense to not stop eating carbohydrates or are we onto something?
Also protein poisoning happens if you don't eat fat, not if you eat too much protein.
This is obviously already true. You would get protein poisoning very quickly long before you hit your TDEE.
First off, do you need a study for that? I'd hate to sound insensitive, but perhaps common sense is a new Darwinism? There's a slew of shortcuts that will cut our lives short.
And for the record I eat a huge amount of protein everyday. At least 1 to 1.2 g / kg of bodyweight. I'm not at risk of protein poisoning (per another commenter) since I consume a large amount of water, fiber as well, and the sources are lean meats rather than powders. Although I admit a weakness in the knees for Quest flavored protein chips. All that said, I'll need a lot more than that to kill me.
Going back, what's common sense is to eat natural foods rather than avoid them. Processed stuff is the real danger, including meal replacement with powders. If people don't even have time to eat due to their jobs, I'd argue they've got a potentially worse lifestyle threat to their health.