We know from films and excerpts from diaries of those around him that Hitler had Parkinson’s Disease. He had pain and tremors in his left arm.
We also know that he had severe gastrointestinal problems, most of which manifested as constipation, diarrhea and flatulence. The problems began when he was a child and nothing during his life ameliorated the symptoms. Doctors think perhaps his stressful home life gave rise to the problems, and continued as he led a life of paranoia and fear and war. Hitler was a classic hypochondriac whose disaffection with meat and most cooked foods grew as he got older. A few years after he took power he decided to swear off anything but raw vegetables and the occasional vegetable soup.
Hitler ate cauliflower and cottage cheese and artichoke hearts and asparagus tips. Dr. Theo Morell, his personal physician, noted in his diary that he had rarely seen a problem this big in a patient. Hitler would have to leave the room after a meal and fart, Albert Speer noted. Of course it was little noted that he was eating an extremely high fiber diet. The problem might have been Dr, Morell, and he may in fact have exacerbated the emotional problems incipient in this paranoid homicidal maniac. Morell took over Hitlers care in 1937 and could not be unseated even by other close friends. Morell, like many doctors in his day was essentially a quack. He fed Hitler Dr. Küster’s Anti-gas pills, which contained toxic substances (strychnine and atropine) that added to his mood swings, mild delirium, his Parkinson’s and his sallow skin.
This regimen was supplemented by an aperçu of other prescriptions for diseases real or imagined: testosterone, cocaine, liver extract, and amphetamines among them. Few knew this but Morell delivered so many injections to Hitler that his arm made him look like a heroin addict. It is quite possible that Dr. Morell’s incompetence did speed the death of Hitler. He was fired a few days before Hitler killed himself.
Sources: “The Secret Diaries of Hitler’s Doctor”, (London, 1983); Waite, Robert G.L., Tony Perrottet, writing for The Economist