Sleep myth: Getting 4 hours of sleep is enough

There are plenty of sleep myths out there. To live your healthiest, happiest life, you need to know what’s true and what’s not. So we are going to start naming myths and putting them to bed. And we’ll start with the myth that people can live well on roughly 4 hours of sleep.

“I’m perfectly fine on 4 hours of sleep.”

We say: False.

While you may get through one or two days on short sleep without hurting yourself or others, it’s not a healthy habit to get into. A common misconception about sleep is that we just need it for daytime energy, and that a few strong cups of coffee in the morning can serve you just as well as a full night’s rest. That’s wrong for two reasons:

• Your coffee will wear off, as will any other short-term fix you apply. But truly restorative sleep should keep you awake and alert all through the day. People think they know their sleep deprivation limit (“Just 4 hours and I’ll be fine tomorrow”), but none of us can afford the risk of finding out when our limit’s been reached by way of an accident at work or on the road. Roughly 4% of drivers over age 18 have fallen asleep at the wheel in the past month.¹
• Sleep gives us much more than just energy. It also enables your body to heal damaged cells, boost its immune system, recover from the day’s activities (e.g. that stressful meeting, hour-long workout, huge restaurant meal), and recharge your heart and cardiovascular system for tomorrow.

“Fine, but I don’t need 7+ hours of sleep.”

We say: It’s complicated.

Earlier this year, the National Sleep Foundation (NSF) released its recommendation that everyone 18 and older get 7+ hours of sleep.² Since then, several WUTS readers have commented that “7 hours” is an unnecessarily high goal. The truth is: Not everyone needs 7 hours of sleep to maximize their next-day energy, productivity and body functions. Some adults may be just fine on 5 or 6,² depending on the day and assuming that the sleep is uninterrupted.

But we still recommend getting 7–8 hours and seeing if you feel and operate better on that much sleep before determining that you’re one of those people who requires less.

The truth.

As with all things medical, the truth about how much sleep we need is slightly different for all of us. We suggest aiming for the hours of sleep NSF recommends (read the article). If you can feel and perform just as well on slightly less sleep, then edit your total sleep goals according to what’s realistic for you.

And as always, if you think you’re getting the sleep hours you need and you still feel tired during the day, talk to your doctor about your symptoms, as well as your risk of having a sleep disorder.

This blog post contains general information about medical conditions and potential treatments. It is not medical advice. If you have any medical questions, please consult your doctor.

References

1. Source: Centers for Disease Control and Prevention (CDC). Drowsy driving – 19 states and the District of Columbia, 2009-2010. MMWR. 2013;61:1033-7. https://www.cdc.gov/mmwr/pdf/wk/mm6151.pdf (accessed May 28, 2015).
2. Source: Hirshkowitz M et al. National Sleep Foundation’s sleep time duration recommendations: Methodology and results summary. Sleep Health 2015;1(1):40–3.