[adrianN]

That is not a very convincing argument. We have evolved eating other lifeforms. That makes it much more likely that our bodies know how to handle the chemicals in plants and animals than the fancy colourings, preservatives and flavours in processed food.

[biofox]

Would you be confident foraging for food in our "natural" environment?

A great deal of plants, fungi, nuts, and fruits are highly toxic. Even staples like rice and fish have high levels of naturally occurring arsenic and lead; and most table spices are lethal in high quantities.

On top of that, there are countless carcinogens, allergens, pathogenic bacteria and parasites in the food chain.

There is a reason lifespan has been increasing.