I also enjoyed ultra processed people. I found the book waffled a bit and some bits were a bit shoe horned in. There is also a tendency towards exaggeration for dramatic effect. The strongest arguments I found were that we have evolved with our food over millions of years and eating is such a core role of any biological organism. Introducing all these edible synthetic products would understandably have unintentional consequences. The other good one is an economic argument: all the food companies want you to consume more, so there is an incentive to make you over eat these products.