Part of Margaret Thatcher's formidable reputation was down to how little she slept. The former British prime minister was believed to get by on just four hours of sleep each night - and she wasn't the only one. Nikola Tesla, the 'grandfather of electricity' was thought to sleep just two hours a night, while Italian politician Silvio Berlusconi only gets two to four hours, and Barack Obama six hours. Scroll down for video New infographic reveals some of the strange sleeping habits of the world's most successful people, and most are below the recommended levels of shut eye. The National Sleep foundation recommends seven to nine hours of sleep a night for 18-64 years olds to maintain a healthy lifestyle
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Margaret Thatcher was believed to get by on just four hours of sleep
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Nikola Tesla, the 'grandfather of electricity', slept for two hours each night
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Winston Churchill would sleep for four hours and take a 90 minute nap
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The National Sleep foundation recommends seven to nine hours of sleep
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Despite Thatcher's example, politicians are the group with the most people who get more than nine hours of sleep each night
@placeholder (right) currently only gets six hours of rest each night