Can you please give your reference for that definitive statement. And what are 'nutritional studies'? Why wouldn't they include the research that led to the list of nutrient recommendations issued by USDA and similar publications in the UK, Norway, France, Australia and many other countries. No conclusions from them? I think there are. There is a truly vast literature on subjects nutritional so it's vital to be very specific.
Separately, when using the term 'ultraprocessed' we should be precise about the processes used. There are many different ones with undoubtedly different effects to different degrees on the nutrients therein.