This is a question we'd never asked before. There's a reason for that, which we'll get to. UPFs (Ultra Processed Foods) have been every nutritionist's favorite punching bag for at least the past 5 years. You know the sort of thing, heavy in sugar, fat and preservatives. Impossible without a manufacturing process, by which we mean you're not growing chicken nuggets in your allotment.

There's been quite a few 'hot takes' on this recently, due to the publication of a study that claims that UPFs aren't the problem everyone thinks they are. Or at least that's how it seems to read on first pass.

The paper itself is paywalled. But Vox has a good summary, if you want the shorter version.

We're usually glad of a contrary study. But something about this one, or at least the headlines, didn't quite sit right with us. It took us a while to figure out why but this is what we came to.

UPFs are actually a pretty new designation, only originating in 2010 in the NOVA food classification system. If we're honest we didn't think of UPF as a 'scientific' term, we assumed it was a colloquialism used to describe 'bad food'. The upshot of this system is that in the article the author states that tofu was classified as an UPF in one study and adding wheat gluten automatically triggers UPF classification.

So, our read of this isn't that in fact UPFs are totally fine for you. This paper isn't really an argument that UPFs are OK. It's an argument that the classification needs sharpening, so it catches the right foods. And underneath that lies a genuine question: is processing itself the problem, or is it what's being processed?

If you read the nutritional information on a UPF, no one is suggesting you should consume it. In fact, please don't. What this is saying is that if you had the same nutritional makeup formed, somehow, from minimally processed foods then the impact would be the same. 

We initially filed this under 'shrug' but on reflection that was due to us just assigning all bad, processed foods to the UPF camp. Basically classifying on 'vibes', as the article mentioned. It's probably the same shortcut everyone else makes. Treating "processed" and "bad" as interchangeable, rather than asking what's actually inside. Which, to be fair, seems to be a similar conclusion to the paper.

So, no, you can't now binge on chicken nuggets and claim the bad juju surrounding them is a conspiracy. High salt, sugar and calorific density along with low fibre are still not your friend.

Here's a counter paper from just a couple of years back, no paywall, if you want a bit of balance. 

Upshot: As you were. Eat well and keep an eye on what's actually in it, not just how it got there.