What are processed / ultra processed foods?

Yesterday I tried to hunt down a definition. The FDA has no definition….it does have some vague concepts. Cleveland Clinic and Mayo Clinic refer to ingredients not normally found in a home.  Then they go on against food dyes and breakfast cereals.  I suspect breakfast cereals are normally found in a home. And in the 1950s my mother used food dyes when making frosting for Christmas cookies.  

So, I find myself sort of like the FDA, I have a vague idea as to what they are, but I have no definition I am comfortable with to guide me.

To me, a food is ultra processed if it contains white flour. Likely also, white sugar. Things that you are unlikely to want to make at home from natural ingredients.

Processed, to me, is something that is made into something not immediately recognizable from the original ingredient(s), like grinding wheat into flour, etc.

This was at least interesting, if not particularly definitive: https://en.wikipedia.org/wiki/Ultra-processed_food

I don't know this is how anyone uses these terms but it might be useful if the distinction between processed and ultra processed is about what you can do in a relatively normal home kitchen. I can grind wheat, but not fractionally distill trans-2-hexenal out of apple pomace. So flour is processed and specific aromatic compounds are ultra-processed.

I don't know. Even then, it doesn't exactly relate to healthfulness or safety. I guess we have to settle for shades of grey.

The AI bot suggested this...

Processed foods are those that have been altered from their original state through methods like cooking, freezing, or canning, and can include items like frozen vegetables or canned fruits.

Ultra-processed foods, on the other hand, are made mostly from substances extracted from foods or synthesized in laboratories, often containing additives like sugars, fats, and preservatives, and include items like chips, sugary drinks, and ready-to-eat meals.

There seems to be a big grey area though. I wonder if it would be better to view it as a spectrum?

An easy definition, just my two cents, anything that is not a fruit, vegetable or a whole food, including meat and diary. Foods that have ingredients added to it.

Bread is a processed food.

Pre-cut or canned vegetable and fruit.

Cereals, cakes and cookies.

I liked Christopher's answer.

To me, a processed food is anything that has been altered in some way by means of cutting, chopping, cooking, freezing, drying, frying, etc.

Ultra processed immediately has me thinking of things produced in a factory or laboratory that the average person could not make in their kitchen, but if you use the normal definition of the words, it simply means lots of processing. Would dicing an onion be ultra processed? There are a whole lot of cuts to get there :)

In today's vernacular, I think processed food refers to foods that are farther from their natural state, in the context of making it less healthy. And I think ultra processed foods is used to mean foods that are even further removed from their natural state... or perhaps don't have a natural state because it's not from a traditional food source... and again the context being less healthy.

I would add so called "natural flavor" as the ultimate indicator of junk food. If the manufacturer had to use it, it means he wants to cheat and cheating ends with robbing and all of it is related to concept of junk food - low or lacking ethics leading to producing ersatz, poisoning the masses who got detatched from their culinary roots.
The other good idicators would be seed oils and their derivatives, artificial colorings and preservatives.
I would not classify bakery products as processed food. Of course it's processed, and the soup is also processed, but there is a difference between 3 ingredients bread and 40 ingredients spongy, toxic concotion sold as "bread".