4. Howard Hughes
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Hughes was an extraordinarily successful businessman, aviator, and filmmaker. As many people know, Hughes had a serious aversion to anything he thought was harboring germs or other contamination. It was after he was involved in a serious plane crash in 1946 that his behavior became even more eccentric. During 1947 he secluded himself in his screening room for four months and lived on chicken, milk, and chocolate while he used containers to relieve himself instead of going to the bathroom. He also ordered his assistants not to speak to him unless he spoke to them first. Hughes was fully ruled by his OCD and whatever other mental illnesses he may have been suffering from when he died in 1976 after a long period of seclusion. At the time of his death, he was also suffering from malnutrition and weighed just 99 pounds.