Having less than seven and a half hours' sleep a night 'quadruples heart attack risk' - Daily Mail 11th November 2008

Sleeping for less than seven and a half hours a night can raise the risk of heart disease by up to four times, say scientists. They blamed the modern trend towards shorter nights' sleep for increasing the risk of suffering a heart attack or stroke. The average Briton gets seven hours' sleep, but a third regularly have five hours or less.

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