Sorry, no citable sources, just reading between the lines of "processed food is bad" and the dissatisfying explanations usually given in that context.

What we do know is that animals and humans have a natural ability to balance their diet (by developing seemingly random cravings?) and that this ability is increasingly breaking down in "western civilisation". It is a small jump from that to the idea that market driven "yummy engineering" could be the perfect setup to find the fault lines in our diet balancing instincts.