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What is the difference between time spent in bed and bank balance? No, this is not the start of a terrible joke, and the answer is less than you might think.
We all have times when we stay up too late and don’t get enough sleep. Think of this as the equivalent of splurging on an expensive dinner: you probably shouldn’t, but your bank balance won’t suffer too much.
This article is part of a special series investigating key questions about sleep. Read more here.
But regularly not getting enough sleep – A problem for many people, as reported by the US Centers for Disease Control a third of adults there get less than 7 hours a night – you can accumulate sleep debt, with real consequences for physical and mental health (see “Why Your Chronotype Is Key to Knowing How Much Sleep You Need”). Like paying off financial debt, sleeping takes planning.
Part of the problem is that we may not know how much sleep debt we’ve built up and how much it’s affecting us. In an examfor example, participants were randomly selected to get 4, 6, or 8 hours per night for 14 consecutive days. At the end, those who got 6 hours or less showed a cognitive deficit equivalent to getting no more than two nights of sleep. However, despite feeling worse after a couple of days, the restricted sleepers thereafter did not necessarily notice that their cognitive abilities continued to decline. “A tired brain can’t perceive how tired it is,” he says Russell Fostera…
