Yes, we read up on the Tim Spector, Chris van Tulleken, listened to the podcasts, yada, yada a couple of years ago, I've always cooked from scratch (I like it, it's better value, nicer food, etc) but since becoming even more aware of it we've cut out the things that were making regular appearances in the cupboards, like biscuits, ice-cream, supermarket bagels and baked goods, the odd ready-meal, fish fingers, salted nuts.
It's not that hard. Sweet cravings are satisfied by a bit of dark chocolate (80% plus) after dinner, or we'll make a cake or a pudding (DH does a fantastic crumble!) from scratch at the weekend if we really want a sweet treat. We have two good bakeries nearby so buying proper sourdough is easy (yes, it's more expensive, so we eat less of it). We were never big consumers of takeaways or sodas, which is a big source of UPFs. I like the occasional bowl of crappy soupy noodles, and DH loves a sausage roll, bless him.
I reckon we're about 90% UPF-free, like we're 90% alcohol free. We're 100% smoking and drug-free, exercise regularly and, if luck holds out, hopefully that's all good enough.