Some processed food does mess your stomach up. Like, freeze dried eat-in-the-forest bags of food.

There has to be some sort of concern at some point? I mean, the stomach might get a too easy job with the food almost predigested?

But mainly, "processed food" is probably just an indirect measure of a bad diet, lots of sugar etc

It is probably true that eating lots of processed food robs your body of the chance to digest unprocessed foods via displacement.

But again, that doesn't mean processing does harm - it's just your responsibility to include "whole" foods for maximum healthfulness.

I think it depends on the definition of "harmful".

Certainly grinding oats into oats flour does not make them dangerous for the body just because of the grinding process.

But it is probably that when they are ground, you use more of X to keep them together, and X is not good for the body. Not a poison but something that makes your body suffer when eaten in too much quantity (say, sugar).

So all in all the processed food brings to your body stuff that it should not in such quantities.

This is like a beer once in a while, which is fine, but two daily will eventually make you sick.

Daily reminder that the term "ultraprocessed food" is a label meant to encompass the complex set of unhealthy things in modern, mass produced food products and not literally about "amount of processing".

I can't never tell if comments like this are genuine confusion from overly-literal people with poor language skills, trolls, FUD from manufacturers or what.

Food is complex. A healthy diet is going to be a multi-variable equation including different fats (omega-3, omega-6, omega-9, etc), proteins (9 different essential amino acids needed in varying quantities), carbohydrates (with varying insulin and other metabolic impact by chain length), vitamins, minerals, fiber (soluble & insoluble). As well as uniquely modern things like artificial colors, emulsifiers, anti-caking agents, anti-microbial preservatives, etc. And then overall calories tailored to an individuals size and level of activity.

It's too many variables to include detailed, nuanced descriptions, so we need to use terms like "ultraprocessed" as a shorthand approximation to capture the diverse set of food products which cause obesity, diabetes, GI issues, cognitive issues, etc.

Name a food product that "causes obesity and diabetes", if calorie-matched.

(Eg if you replace 150 calories of the closest unprocessed equivalent with 150 of this ultra-processed version)