What research are you referring to that says a animal based diet is "harder" on the human body than a vegan diet?
What do you think we would be eating if we ran down and killed the animal that we are not getting now. We have started to eat organ meats but many carnivores and native peoples dont/didn't eat organs.
Everything I have seen and my first hand experience says meat is easier for the human body to digest than plants. Fermented foods are mainly of benefit to people eating carbs, most people see a increase in fecal biome diversity upon going carnivore.
I agree that fermented vegetables are one of the less irritating plant based foods because of the fermentation but not necessarily a benefit to a carnivore
Thanks for commenting
RE: Yesterday's carnivore lunch