I’ve seen this directive multiple times through the years, and I still disagree with it. It strikes me as the kind of rule of thumb dreamed up by someone in need of attention who got through school without taking a single chemistry course.
Case in point: how many people would see a prepared food listing dihydrogen monoxide on its label as healthy? What is dihydrogen monoxide? Water.
The other point repeaters of this directive fail to grasp is that many of the naturally occurring molecular components of fruits, vegetables, nuts & the like carry chemical names that can be quite long & difficult to impossible to pronounce. So just because an ingredient on a label has a seemingly unpronouncable name does not mean it is unhealthy.