Alcohol and Sleep

Does alcohol help you sleep? 

The short answer is no. Happy hour may in fact lead to some frustratingly unrestful hours later on when it’s time to catch some zzz’s. When it comes to drinking alcohol before bed, you might fall asleep more quickly, but how does alcohol affect the quality of your sleep once asleep? Let’s find out.

Because alcohol acts as a central nervous system depressant, you may think that a drink before bed can help reduce anxiety and help you sleep better. You might not be surprised to hear that many people can’t sleep without alcohol, and rely on it to help them sleep.  

Despite the popularity of a “night cap”, the science says a drink before bed doesn’t help and may actually hinder sleep quality.  Furthermore, relying on alcohol as a sleep aid can lead to alcohol dependence.

So, while Esquire magazine offers an entire article on the best alcohol for sleep[1] — spoiler alert, it’s all about the ritual — in reality, a drink before bed does not improve sleep quality.[2]  As it would turn out, alcohol actually interferes with your sleep patterns, reducing the time you spend in REM sleep.

If you’re asking yourself, “What is the best alcohol for sleep?” then you may need to reexamine your sleeping habits. Let’s dive into the link between sleep and alcohol and examine how alcohol can interfere with a good night’s sleep.  

Even if you don’t use alcohol as a sleeping aid, you should be familiar with how a drink or two at dinnertime can interfere with your sleep and circadian rhythms. 

The purpose of this article is to help you better understand the relationship between sleep and alcohol.  Learning about how alcohol affects sleep can help you improve your sleeping patterns and sleep quality, and help you explore alternatives to alcohol, which, as a sleep aid, can be dangerous and habit-forming, not to mention ineffective.

How does alcohol affect sleep?

Alcohol’s effects on sleep may not be what you think.  Alcohol can make you feel more tired, and perhaps help you doze off. These qualities may make alcohol seem like an attractive sleep aid for someone with insomnia. However, alcohol does not promote a good night’s sleep.  

According to one study, the science says that a blood alcohol concentration (BAC) of about 0.04 is the threshold for when sleep begins to be disrupted. This is equivalent to approximately one drink. In order to avoid these ill effects, it is recommended to refrain from drinking alcoholic beverages at least two to three hours before bedtime.[3]

For the night cap drinker, the sleep you get after just one drink is of lower quality.  This is because alcohol consumption interrupts the normal sleep phases that your body undergoes every night, so that you do not spend a sufficient length of time in the requisite sleep phases to get a fully restorative and refreshing night of sleep. There are many other better options to help you get better sleep. 

Normal sleep stages — an overview

As mentioned, while alcohol can make you feel tired, there’s no evidence that it actually improves your quality of sleep. There is however a strong body of scientific evidence indicating that alcohol interrupts the normal stages of sleep that our bodies and minds undergo every night.[2]

In order to understand the sleep, first, let’s take a look at how a normal, healthy night of sleep progresses.  To summarize our nightly sleep cycle, there are four sleep stages that we experience during a full night’s sleep.[4

These stages are broadly divided into REM, or rapid eye movement and non-REM or NREM. There are three stages of NREM. For the purpose of keeping things simple, we’ll just refer to the non-REM phases as N1 through N3. After the final stage of NREM (N3) we enter REM.

There used to be a fourth stage of NREM but in 2007 in the interest of clarity, researchers stopped using N4 and began just using N3 to represent deep sleep. 

The first two sleep phases, N1 and N2, are considered “light sleep.” During these phases, we may be in a shallow state of sleep. In the earliest stage, N1, we may even be between sleep and wakefulness. In N2, and our breathing and heartbeat start to become regular.

The last phase of NREM is N3, also referred to as “slow-wave sleep”, “deep sleep”, or “delta sleep”.  This stage is thought to be particularly important for the body to recuperate as well as for memory consolidation.[5][6]

REM sleep, the last stage of sleep, is the stage in which we are engaged in active, vivid dreaming. The brain is very active during REM sleep, and your heart rate and breathing gets faster during this phase. 

This is the sleep phase where the brain is known to undergo processes essential for learning and memory.  REM sleep is a restorative phase of sleep that helps our brain to consolidate memories, improve immune function, and conduct maintenance to repair the body’s cells and tissues.[7]  

Adults typically spend about 20% of sleep in REM.  We cycle through all of these different phases each night, spending most of the time in REM in the second half of the night.  In a normal night’s sleep, our first REM stage may last only 10 minutes, and the final REM stage may last up to an hour.[8]  REM sleep is known to stimulate the brain regions involved in learning.[9]

How does alcohol interact with REM sleep?

Now that we’ve discussed the different stages of sleep, let’s take a look at how alcohol affects a normal night’s sleep. 

A 2013 review of 27 studies examining the link between sleep and alcohol found that alcohol does not improve sleep quality.[2]  Furthermore, the study found, the consumption of alcohol changed the amount of time our brain spends in the different sleep phases each night and led to more frequent middle-of-the-night awakenings.  

The study found that while alcohol can help people fall asleep more quickly and sleep deeply in the first half of the night, total REM sleep was reduced after alcohol consumption.[2]  The most substantive sleep disruptions were seen in the second half of the night. Specifically, the researchers found reductions in REM sleep duration and delayed REM sleep onset at moderate and high doses of alcohol, defined as 2-4 standard drinks and more than 4 standard drinks, respectively. Of the 11 all-night sleep studies evaluated with significant results, reductions in REM sleep percentages ranged from .7%-11% in a dose-dependent manner.[2] 

Taken together, this indicates that alcohol may reduce the learning and memory consolidation processes that occur at night, leading to a poor night’s sleep and feeling groggy and tired upon waking, not to mention the next-day hangover. 

So, while alcohol can make one sleepy and promote the lighter phases of sleep, evidence suggests that it may disrupt our sleep phases, especially REM, which is considered the most restorative phase of sleep.  

This is one reason why doctors do not consider or recommend alcohol as a sleep aid.  Secondly, alcohol can make one more prone to sleepwalking and talking during sleep, and can cause memory problems.  A third reason is that relying on alcohol for a sleep aid can promote dependency on the substance, which can lead to alcoholism and a host of other problems.

Alcohol and sleep quality

The negative effects of alcohol extend beyond reorganization of the sleep phases.  Alcohol, as a nervous system depressant, can also cause sleep apnea, or pauses in breathing which can occur throughout the night.[2]  People diagnosed with sleep apnea should therefore exercise caution when drinking close to bedtime, as alcohol can exacerbate sleep apnea.  

Alcohol can also aggravate other sleep disorders such as sleepwalking and restless leg syndrome,[9] and interact with a variety of medications.  And the more one drinks before bed, the more pronounced the negative effects on sleep will be.

So, if you’re asking yourself, “should I use alcohol to fall asleep or stay awake and sleep when my body falls asleep naturally?,” it’s better to look for other options aside from alcohol to help you fall asleep.  

Remember that alcohol is not a suitable sleep aid, and, as the science shows, it actually interferes with your body’s natural sleep phases.  While alcohol may promote drowsiness and a feeling of being tired, it also has effects on REM sleep that make your slumber choppy and less restful.  

Rather than turning to alcohol, it’s better to stay awake and let your body fall asleep naturally, without disrupting effects of alcohol on REM.  

Alternatively, there are many suitable sleep aids available for people who are trying to get more shuteye. Check out this article on natural sleep aids or this one on essential oils for sleep. Try our some of our free Remrise meditations, which will help slow your mind in preparation for sleep. 

How can I limit the negative effects of alcohol on my sleeping patterns?

You may want to consider the relationship between alcohol and sleep as part of the larger balancing act of health. Like any balancing act, the sleep-alcohol connection can easily be thrown off, which can affect both your health and your quality of life.

People who drink alcohol and want to get good quality sleep should be mindful to avoid consuming alcohol close to bedtime.  A glass of wine or two at dinner may be the norm for some people, but if consumed too close to bedtime, these drinks can cause significant disruptions to one’s normal sleeping patterns.  

That’s why you should make sure to stop drinking alcoholic beverages at least two to three hours before bedtime to ensure that it will not disrupt your sleep. Those who experience difficulties sleeping should consider solving their problem without alcohol, as it’s not a sleep aid.  

As we’ve discussed above, alcohol promotes unrestful sleep, can increase the risk of sleep disorders such as obstructive sleep apnea and sleepwalking, and can interfere with normal memory consolidation and other restorative processes that occur during sleep.

References

    1. Wondrich, D. 2014.  “An Endorsement of the Nightcap.”  Esquire Magazine. Accessible at https://www.esquire.com/food-drink/drinks/a24179/nightcap-endorsement-0913/.
    2. Mann, D. 2013.  “Alcohol and a Good Night’s Sleep Don’t Mix.”  WebMD. Accessible at https://www.webmd.com/sleep-disorders/news/20130118/alcohol-sleep.
    3. Roehrs, T., et al.  1999. “Ethanol as a hypnotic in insomniacs: self administration and effects on sleep and mood.” Neuropsychopharmacology.  Accessible at https://www.ncbi.nlm.nih.gov/pubmed/10063488.
    4. Harvard Medical School.  “Natural Patterns of Sleep.”  Accessible at http://healthysleep.med.harvard.edu/healthy/science/what/sleep-patterns-rem-nrem.
    5. “Slow-wave sleep.”  Nature. Accessible at https://www.nature.com/subjects/slow-wave-sleep.
    6. The significance of sleep onset and slow wave sleep for nocturnal release of growth hormone (GH) and cortisol. Neuroendocrinology. Accessible at: https://www.sciencedirect.com/science/article/abs/pii/0306453088900212                                                               
    7. WebMD.  “What are REM and Non-REM Sleep?” Accessible at https://www.webmd.com/sleep-disorders/guide/sleep-101.
    8. Cleveland Clinic.  “Sleep Basics.” Accessible at https://my.clevelandclinic.org/health/articles/12148-sleep-basics.
    9. PsychCentral.  “The Importance of REM Sleep.” Accessible at https://psychcentral.com/lib/the-importance-of-rem-sleep-dreaming/.
    10. Restless Leg Syndrome Foundation. “Triggers for Restless Leg Syndrome.”  Accessible at https://www.rls.org/file/triggers-052016.pdf.