But its true that not healthy food that has some additional protein mixed in ain't magically healthy.
We as a specie haven't eaten as many protein as today since the invention of agriculture millennia ago, so idk what you mean by “civilization diseases” but if you mean diabetes and such, then it's clearly wrong.
We're currently eating too much and too much sugar though.
Now if people choose a diet low in protein/calories ratio, they'll have a tendency to ingest more calories than people who eat protein rich diets. Try eating eating 300 g of cheese/meat/tofu in one meal, it'll be difficult. Eating 300 g of chips/fries is something many people can absolutely do, if the chips aren't too salty.
One significant difference between our modern western lives and the lives of people tens to hundreds of years ago is IMO that people back then quite automatically used up all the carb calories of their comparably protein diluted diet because life required much more physical activity and came with less home heating than today. Today, most people will just not expend much of the caloric energy of carb rich diets and thus develop metabolic diseases and such.
A carb rich diet is usually fine as long as you expend the energy via physical activity.
I don't know where you get the idea that eating 300g of meat is difficult …
> A carb rich diet is usually fine as long as you expend the energy via physical activity.
Any balanced diet is fine if you ingest no more energy than you spend, which is exactly what I said: people today are eating too much.
You're right, 300 g of meat isn't much of a challenge. The more appropriate comparison would be between 300 g of chips and an equal amount of calories in some protein rich food like meat. That should be much more challenging.
> .. people today are eating too much.
Yeah, the important question is: why are they eating too much?
I assume that a lot of it is unintentional. Overeating mostly happens because people aren't aware of a few simple mechanisms or are misunderstanding them, not because the world is hard. Mechanisms which they could quite easily use to overeat less or avoid it altogether, instead of falling prey to them.
Just telling people that they're eating to much doesn't help in any way. People need to know why and how they can quite easily change it.