For me, it has to be the UK since British food tends to be heavily processed along with a fixation on fish & chips, bangers & mash, pies and pastries with high fat content (most feature at least a fried item beside them, whether it’s an English breakfast with a hash brown) but not on the level of unhealthy to that from American cuisine.
I’d love to hate on the British, but the premise of this question is just weird. What’s healthy is very subjective and situational.
Hmm I’d get your point if the question was “who has the best cuisine” but healthiness is a pretty objective (if complex) factor.
Subjective as dependent on person. A person who is undernourished will need different food from someone who is overnourished. Allergies and intolerances play their part. I didn’t intend to claim that healthy food is not based in material reality.