

Processed unhealthy foods are generally viewed as the items that have been stripped down in to some degree and then reassembled with ingredients like sugar, preservatives, flavors, dyes, stabilizers, etc.
Many studies have shown that yes, indeed, there are processed foods that are inherently unhealthy. We don’t need to play with semantics of what “processed” means to split hairs in an effort to be right.
Wasn’t it new in the ‘70s? Some papers put it as officially recognized (in the US at least) in the ‘60s. I’m not sure when medicines became available for it though.