"The Dalai Lama goes into a Pizza parlour and says "Can you make me one with everything?" The Dalai Lama asks his translator for a translation and then says "Ah, Pizza shop" and goes back to listening intently to the interviewer, who repeats the joke and, laughing, tries painstakingly to explain the joke, "Can you make me ONE..." (pauses for emphasis as he tries to demonstrate to the Dalai Lama by holding his hands together as if in prayer) "... with EVERYTHING" (the interviewer gestures a large space with his hands and starts to laugh at the hole he's digging for himself). The Dalai Lama again asks his translator for some clarification and then resumes concentrating on the interviewer intently and smiling, he says, "Theoretically impossible" upon which the interviewer laughs with embarrassment and says, "I knew this wouldn't work" upon which the Dalai Lama starts to laugh.
You might think this was the end of the joke, and I guess you're wondering, "Where's the connection with Crohn's and Mind-body interaction?", well wonder, no longer......
Here is a comment posted on the same page where this interview was reported. Continuing the joke's theme it provides a lovely illustration of the Lama's reply:
"The Dalai Lama gives $100 and waits, but the waiter says (drum roll), "the change comes only from within"."
There you go!