It's a lot easier to define unprocessed than processed. Unprocessed is just how it is from plants or animals with little or no alteration. Processed is altered, like through mechanical action or chemical alteration, and also different things mixed together that are not in nature. The problem here is there are so many directions to go doing that, and so many degrees.
But in the end it doesn't matter, since it is becoming so overwhelmingly clear that it is best to stick with unprocessed.
> Unprocessed is just how it is from plants or animals with little or no alteration. Processed is altered, like through mechanical action or chemical alteration, and also different things mixed together that are not in nature.
That's a clear definition, but it's extremely sweeping! It's also very clearly not the definition being used by this study, which had an "unprocessed" menu that including wheat flour pasta, cooked food, frozen food, food with herbs and spices from all over the world, food that had undergone chemical changes, etc.
> But in the end it doesn't matter, since it is becoming so overwhelmingly clear that it is best to stick with unprocessed.
By your definition, this study does not support that conclusion.
>By your definition, this study does not support that conclusion
Not this study alone, but a great many studies to which this study adds one more bit of evidence. Which is how it generally goes in research.
When I said "in the end it doesn't matter" I meant having a precise definition of processed didn't matter for the question what our diet should be. I should have made that clearer.
> to which this study adds one more bit of evidence.
This study does not support your conclusion, and so adds no evidence to support that conclusion. It's not even studying the sort of diet you're talking about!
> I meant having a precise definition of processed didn't matter for the question what our diet should be
No, it really does matter. If you're trying to argue that some specific food or processing technique is bad, then a study that had all participants consume it can't be used to show that it's actually harmful. And by your definition, that's what this study did - it had everyone consume highly processed foods, and some of them had good outcomes. That undermines your conclusion; it does not support it.
Perhaps the above comment is accurate in the sense that a raw, paleo diet is healthiest for humans, or even the only truly healthy diet. (Though I've yet to see any strong studies claim that it beats a Mediterranean diet, much less a great many studies.)
But even if that's true, it's an entirely different question from "what's up with modern ultraprocessed foods?" This study was contrasting foods like "normal" pasta with canned ravioli and finding a difference. Since "everyone only eat raw food" is an unlikely and unpopular outcome, it's absolutely worth finding what's actually problematic within the enormously broad sweep of "processed".
It's much easier to define unprocesesd, definitely, but what concerns me is that processed food in general doesn't seem to be the issue. There are cuisines which have depended very heavily on processed foods for centuries, and yet the obesity question is new within the last 100 years. In particular, bread, cheese, cured meats, and pickled anything are all clearly processed. And yet historically Norwegians haven't ended up with obesity than temperate cultures eating things like unprocessed rice and fresh fish, or minimally-processed corn tortillas.
Perhaps this will just come down to modern diets having a higher percentage of processed foods and more calorie availability. Even in Norway in the winter, potatoes and some fresh game would be part of the diet. And on a ship or snowbound wheat farm with only processed food available, food might be scarce enough that people weren't freely eating to satiation.
But even wealthy urbanites with plentiful access to processed calories don't seem to have become obese with the consistency of modern people, and this study and theory aren't endorsing a raw or paleo diet. Bread, yogurt, and even pasta and butter are technically processed foods. Canned ravioli and store-bought cake are being contrasted with their home-made counterparts. And I suspect that's correct: even if a raw/paleo diet turns out to be best, 20th century ultraprocessed foods have caused new problems not seen with earlier processing. That means there's another definition worth asking about.
If the "mixed signals" theory is right, there won't be a single culprit. Sugar alcohols are pleasant and create anticipation, but don't follow through with energy. Low-fat yogurts don't trip fat-based satiation fully, and yet substituted sugar is higher-calorie per bite than fat. Perhaps the rule we'll find that degree of processing doesn't matter, but any food 'impersonating' something else is a risk for overeating.
Regardless, I'd like to know what aspect of "industrial" food is causing different outcomes than merely non-natural foods.
But in the end it doesn't matter, since it is becoming so overwhelmingly clear that it is best to stick with unprocessed.