I følge Yahoo News var det diarre der var årsagen til at Abe måtte trække sig fra premierministerposten.
"Abe said he has been struck by ulcerative colitis, a bowel illness caused by ulcers, at least once a year since he was 17.
Abe, whose grandfather was also prime minister, was groomed for politics from childhood. He said he would never forget the shock when the illness first hit him as a young man.
"To mention an indelicate matter, I rushed to the lavatory after having keen abdominal pains and saw the basin all red with tremendous bleeding," he said.
"Bleeding causes slight anaemia. More than anything else, though, you feel depressed as you see fresh blood every time you go to the toilet," he said in an article contributed to the major conservative monthly Bungei Shunju.
Abe said the illness usually made him "feel the need to relieve my bowels every 30 minutes."
"You can never get a good night's sleep as you shuttle between the bed and toilet," he said.
"The need to go to the toilet many times a day hampers election and other political activities very much," he said, adding his wife, Akie, once made a tearful plea to him to quit his political career.
Abe said his health deteriorated in late August, when his stomach was upset by local food during his tour of, and .
He said the final straw came in September, when he was so sick he skipped lines of his policy speech in parliament.
"Once ulcerative colitis worsens, I would need to go to the lavatory 30 times a day. It would be absolutely impossible to perform the heavy duties of prime minister," he said."