There’s a difference between how much sleep people need and how much they get. Most research indicates that adults show the lowest average mortality rates with about seven hours of sleep. Life expectancy drops if you go more than two hours either side of this.
But if you have a busy life, sleep is often the first part of your schedule to get cut, so people who survive on just four or five hours may be doing just that – surviving, rather than thriving (Prime Ministers, like Margaret Thatcher and Gordon Brown are famed for getting by on just a couple of hours a night).
At the other end of the scale, some people don’t sleep very restfully. Stress, a bad bedtime routine or an uncomfortable bed can also mean you need more hours in bed to get the same amount of rest.
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