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Why do we need sleep? Article



Ever wondered what goes on in your brain while you’re asleep? While you may not remember those 7 to 8 hours you spend every night with your eyes closed, your brain does—and it keeps active and busy the whole time.1 Find out just what goes on while you sleep, and why snoozing is so important to your mind and body.

You’ve Got Sleep on the Brain

Why we sleep is a popular topic—and one that is still a source of debate for scientists and sleep researchers. We do know that sleeping is not a passive activity, but one where our brains keep quite busy processing information, consolidating memories, and conserving energy.1 Brings a whole new meaning to the expression “I could do that in my sleep,” doesn’t it?

Not Just a Case of the Mondays

Feeling crabby and groggy the morning after a poor night’s sleep? You’re not alone. One of the most common early indicators of sleep loss is mood change, most often expressed as irritability and difficulty controlling emotions.2 Besides making you snap at the person who took the last donut, lack of sleep can also cause you to feel bleary-eyed, tired, and inattentive. That’s because sleep allows the body and brain time to recuperate from the previous day’s activity. Without adequate sleep, you may carry over stresses, worries, and a general cranky-pants attitude.

Lack of Sleep Makes a Big Impact

If missing out on good sleep for one night makes us less alert, what does lack of sleep over multiple nights do to our mind and body? According to one study, even missing just two hours of sleep per night for one week was associated with a significant increase in sleepiness, and a reduction in psychomotor performance.3 Wait, psychomo-what? Psychomotor performance is when your brain tells your body to do something, typically a small or mundane activity, such as brushing your teeth or turning right at the next light. But those small activities are pretty important when your lack of sleep means that you forget to do them. Which can lead to that foggy, panicked thought that breaks through your midday meeting: “Hold on—did I forget to close the garage door?!”

The Inside Track on Falling Asleep

Luckily, for people with occasional sleeplessness, there are many safe and effective sleep medicines available over-the-counter—such as ZzzQuil™ Liquid or ZzzQuil LiquiCaps® Sleep-Aid Products—to help you get the sleep your body and mind need. And as for the future of slumber research, leaders in the fields of sleep and medicine are continually advancing research into the mechanics of sleep, discovering how it plays an important role in our lives, and brainstorming solutions to achieving a more complete restorative sleep. Want to show your sleep smarts? Prioritize catching your Zzz’s—starting tonight.4

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U.S. Department of Health and Human Services National Institutes of Health (NIH) and National Heart Lung and Blood Institute. Your guide to healthy sleep. NIH Publication No. 11-5800. September 2011. Available at: Accessed 15 March 2012.
Bonnet MH. Acute sleep deprivation. In: Kryger MH, Roth T, Dement WC, eds. Principles and Practice of Sleep Medicine. 5th ed. Philadelphia, PA: Saunders/Elsevier; 2011:54-66.
Vgontzas AN, et al. Adverse effects of modest sleep restriction on sleepiness, performance and inflammatory cytokines. Journal of Clinical Endocrinology & Metabolism. 89(5):2119-2126. Available at: Accessed 20 March 2012.
National Sleep Foundation. How much sleep do we really need? Available at: Accessed 18 January 2012.