Thanks to all for advice.
I had one big raw fruit/salad meal about once every three weeks in the past four months, usually on the occasion of buffet socials. I did not experience digestive problems. Maybe my carb digestive enzymes/bacteria have never retired?
The reason I am thinking of "going cold turkey" to high-raw-fruit is that I hope to eat raw animal flesh as much as possible until the moment I leave U.S. (the land of bountifulness) and fly to Taiwan, where I do not expect to be able to eat raw quality animal flesh for a couple of weeks (I have to do research on animal food there and I will have a string of socials and short trips to different cities...)