Can you really catch up on sleep on the weekend?

Sleep is a precious commodity, but many of us have trouble getting enough of each night. We set early alarms to face the busy days ahead. And after long days of work, caring for our family and dealing with all the chaos life throws, we often stay up late into the night.

At the end of a long week, we often look forward to shutting off the alarm and sleeping in. Or maybe we look forward to a few blissful weekend naps.

But do naps or sleeping in actually help us recover from sleep debt, that lost sleep during the week? Scientists recently reviewed years of research and recently released their conclusions about sleep consistency — going to bed and getting up at the same time each day — as well as the best way to recover from sleep debt.

For years, scientists wondered if it was even possible to eliminate sleep debt after the initial sleep loss. Now, a new study of the existing research suggests that while extra sleep on the weekends may not completely eliminate your sleep debt, there’s no reason to worry about the negative effects of sleeping in or taking a short nap when necessary.

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What Is Sleep Debt?

Sleep debt simply refers to the deficit between how much sleep you need and how much you’re actually getting.

Just how much sleep should we be getting? The Centers for Disease Control and Prevention recommend an average of seven to eight hours of sleep each night for adults.

So, to calculate your sleep debt, let’s say you only get six hours of sleep each night during the weekdays. That’s one to two hours less than health experts recommend each night. When you add that up, you’re looking at five to 10 hours of sleep debt per week.

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Duration Is Critical With Sleeping In and Naps

In a research review released by the National Sleep Foundation in September, a group of scientists narrowed down 40,672 relevant publications for their study to 63 papers that discussed sleep deficiency and the benefits of sleeping in or napping.

After looking through extensive research, the panel of scientists announced an agreement on two main conclusions:

1. Individuals should work on finding a regular sleep schedule to get the recommended hours to prevent sleep debt; however,
2. When adequate sleep duration is not possible on work days, one to two hours of catch-up sleep on weekends may be beneficial.

That short window of time can provide enough extra rest to help reduce overall sleepiness without affecting our body’s circadian rhythm — our natural wake and sleep cycles during the day.

According to the Centers for Disease Control, short-duration naps are also a healthy way to chip into our sleep debt. But keeping it short is key: Research has shown that naps lasting longer than one hour can lead to sleep inertia, leaving the person feeling worse than before they went to sleep.

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Sleep Debt’s Cost: Obesity, Memory Loss and More

Beyond feeling tired on a regular basis, research has also shown that sleep debt (also known as sleep deficiency) can cause long-term side effects for our mental and physical health.

Dr. Stuart Quan, a contributing editor to Harvard Health Publishing and a sleep health expert, wrote about the correlation between lack of sleep and weight gain.

“A number of large studies involving thousands of adults have generally found that short sleepers (defined as five hours or less per night, but sometimes six hours or less) were up to 45% more likely to be obese,” he wrote on the Havard Health Blog.

Weight gain from lack of sleep likely happens for a combination of reasons, according to Quan and other sleep health experts, including:

• Fatigue often leads to less-healthy food behaviors, including skipping meals, eating more often and eating more junk food to keep energy up.
• Lack of sleep can cause the body to develop insulin resistance and glucose intolerance, which contribute to type 2 diabetes

From a mental health perspective, sleep debt impacts our brain by reducing our ability to focus, plan and even use our short-term memory, according to Jessica Langbaum, who has a Ph.D. in psychiatric epidemiology and serves as the director of the Alzheimer’s Prevention Initiative in Phoenix.

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“Too little sleep or inadequate sleep on a regular basis means the brain isn’t able to encode, consolidate and reconsolidate memories,” Langbaum told Banner Health. “Numerous studies have found that loss of sleep also impairs attention and executive functions, like focus and planning.”

So what can you do? Fortunately, the recommendations from the National Sleep Foundation scientists gave us two simple solutions: Work on your sleep consistency, and go ahead and sleep in a little on the weekends.

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