Over the years, we have heard that JFK suffered from an illness that he had kept well-hidden from the general public. Graves disease, I had always thought, was the identity of that illness.
However, during this special, I'm almost sure that Sawyer said that that the illness was "colitis, or celiac disease." In a quick Internet search, I have discovered some entries that also discuss the connection. Very intriguing . . . more later . . . !