When we were in Portland Oregon two years ago for the International Master Gardener's Conference, the hotel restaurant had an excellent soup made from Jerusalem artichokes. I can't say I noticed any gastric distress from it, and I had it at least 3 times.
Based on the research I did, this is not a plant I'd want to try to grow, though.
When we lived in Germany, I remember helping some German friends, farmers, harvest these in the fall, to feed to some of their animals. Cows? Pigs? I don't remember. They also ate them boiled or thinly sliced in salads. I did not like them, so never cooked with them.