" At the very least, they cause our bodies to have to spend a vast amount of energy/resources processing them (hence preventing the body from using those resources & energy to heal itself). "
The liver is supported by natural foods in their whole state. When they are processed it creates toxicity. Imbalance occurs. (over simplified).
There are other factors involved such as the amygdala and the adrenals which is why some people can become sensitive to even otherwise healthy foods. This happens due to interference at several levels (physical, emotional, mental, etc). In essence the body becomes confused due to interference. When we remove the interference the natural template of our bodies can bring about a balanced, health state. A metaphor is it is like taking a blind fold off and being able to see.
To do this we need to remove toxins, supply vital nutrients, and reinstate proper flow. What I see in the alternative field and especially in the mainstream field of health is an over complication of health which just adds more interference.
This is why people like Max Gerson had such a wide reaching effect on peoples health and in so many conditions. He understood that removing interference, supplying optimal nutrition and optimizing flow (which is part and parcel of removing interference) is the key to regaining health.
BTW, I think the Hippocrates Institute is doing good work in regards to these principles as well. The main difference between them and Gerson's institute is the use of all living foods including sprouts where as Gerson is not using sprouts because they have found some bad reactions in some cases. Also Gerson uses some cooked foods.
Each method is leaps and bounds better than anything in the healing arts as far as flooding the body with optimal nutrition goes.
I wish that Max and Ann Wigmore could have worked together and shared insights. Max did co-respond somewhat with Budwig and changed his protocol a bit concerning good fats. Then he took it even further. One thing I liked about Max is he was not set in his ways and changed things as new data revealed itself.
Just supplying another perspective on what you already know.