For example, I am pretty sure, given my own experience, that the body needs to produce much less stomach acid when eating mostly raw foods.
I'm not so sure. Stomach acid is necessary to denature protein. Cooking already denatures protein, so that effectively less stomach acid is needed?
I mean the stomach essentially is like an oven, except it breaks food down chemically, not by heat. I'm not a chemist, but logically at least equally or likely more acid would be needed for raw food.
edit: found a nice article which may help (it helped me) understand:
http://ecologos.org/denature.htmThe conclusion is that high heat results in structures that are harder to break down, so in this case more acid and longer stay in the stomach may be necessary. Heating to 60-70C though, just enough to denature most protein, would lead to needing less acid and easier digestion, in my opinion.