Alcohol Harms Your Sleep: Here's How
The nightcap -- a fancy cocktail or glass of wine to wind down the evening -- holds a powerful place in the American imagination. Drinking in the lead-up to bedtime, though, can have significant negative effects on sleep.
For many people, a drink before bed brings relaxation and makes it easier to fall asleep, but not all sleep is created equal. Alcohol can interrupt the body’s normal sleep processes, reducing sleep quality and risking fatigue and sleepiness the following day.
In this guide, we’ll provide in-depth information about the ways that alcohol affects you during sleep and why it can be detrimental to the goal of getting truly restful sleep.
How Does Alcohol Affect Sleep?
The relationship between alcohol and sleep is complex. Alcohol affects the brain and body in a number of ways, and those effects can be varied depending on how much alcohol is consumed, a person’s tolerance levels, their metabolism, genetics, and other factors.
Despite all of the factors in play, a key takeaway is that alcohol can meaningfully harm sleep and make a person inclined to suffer from sleepiness the following day. Some research even estimates that alcohol may be responsible for up to 10% of cases of insomnia.
Additionally, alcohol consumption, especially heavy alcohol consumption, and sleep disturbances have a reinforcing relationship. People with sleeping problems may turn to alcohol to self-medicate and try to fall asleep. At the same time, alcohol can disrupt sleep, and studies have indicated that regular sleep disruptions increase a person’s risk for alcohol problems.
The following sections explore alcohol’s effects in more detail in order to better understand how this substance negatively impacts sleep.
What Happens When You Sleep After Drinking Alcohol?
Unlike many other drugs, alcohol can function as both a stimulant and a sedative. The exact ways that it causes these diverging responses is not fully understood, but research has recognized that alcohol’s effects are multi-faceted.
Alcohol acts on numerous neurotransmitters and chemical targets within the brain. Neurotransmission is how the cells in the brain communicate and ultimately carry out the functions of the body.
Many of the neurotransmitters affected by alcohol are directly involved in regulating sleep processes, which is why alcohol can have such a profound effect on sleep.
How Does Alcohol Affect Sleep Architecture?
One of the main ways that alcohol interrupts sleep is by negatively affecting sleep architecture and the patterns of our nightly rest.
What is Sleep Architecture?
A person’s sleep architecture refers to how they progress through the sleep cycle.
While the term sleep is used in a broad sense, we actually have discrete stages of sleep. Collectively, these stages are referred to as a sleep cycle. Each cycle lasts between 90 and 120 minutes.
Four stages make up the sleep cycle. The first three are known as non-rapid eye movement (NREM) sleep, and the fourth is REM sleep.
- In stage 1, sleep is very light, and it is easy to be roused back into a state of wakefulness.
- In stage 2, our body moves into a deeper sleep including changes in brain waves and reductions in body temperature and heart rate.
- In stage 3, brain waves slow way down, and it is much harder to be woken up. This stage is thought to be important for restful sleep.
- REM sleep is the last stage. In REM sleep, brain activity picks up to a level similar to when we’re awake, which is why we have the most vivid dreams during REM sleep. REM sleep may be helpful for memory, cognitive function, and emotional processing.
Does Alcohol Change Your Sleep Architecture?
This figure shows the direction of sleep characteristics while drinking and during alcohol withdrawal compared to non-drinking (baseline) subjects.
Yes. Numerous research studies have shown that alcohol alters the normal progression through sleep stages.
When alcohol is still in someone’s system and they go to sleep, REM sleep is suppressed during the first half of the night. Later, when the alcohol has been metabolized, there is a “REM rebound,” in which the REM sleep period is longer than normal in each sleep cycle.
While this might sound like it all evens out, that’s not the case. The uneven sleep cycles create a higher propensity for being awoken and for lower-quality, lighter sleep during the second half of the night.
These effects can become amplified with higher levels of alcohol consumption and with chronic alcohol use. The exact changes to sleep architecture may vary for each individual, but on the whole, it has become clear that alcohol alters the standard sleep cycle that our bodies depend on.
How Does Alcohol Affect Sleep Quality?
One of the primary reasons we need sleep is so that we can be awake and aware the following day. Whether it’s driving, taking care of family, or performing daily work obligations, a well-rested person performs at a higher level and with lower risk for accidents.
Most people know that drinking can bring a hangover the next day that can come with all sorts of symptoms including headache, nausea, fatigue, irritability, and sensitivity to light and sound. But a hangover is typically thought of as an outcome of drinking to excess, and most people assume that if they don’t drink that much, they can avoid next-day effects.
Researchers have found, though, that there are carry-over effects even many hours after stopping drinking. In one study of young pilots, performance in a flight simulator was impaired even 14 hours after having finished drinking and when there was no trace of alcohol in their blood.
Impacts on sleep quality may be related to the way that alcohol disturbs the body’s system of sleep-homeostasis. This system balances our drive for sleep with signals for wakefulness, such as from daylight.
The wakefulness signals are part of the circadian alerting system and how we keep our mind and body in sync with our local day-night cycle. The equilibrium between our drives for sleep and wakefulness plays an important role not just for sleep but for our overall physical and emotional well-being.
The way that alcohol interferes with this system can differ depending on the individual and situation, but this interference creates sleep disturbances and reduces sleep quality.
How Does Alcohol Affect Breathing and Sleep Apnea?
Under the influence of alcohol, the muscles and tissues in the back of the throat become loose and more relaxed. In the process, the airway becomes constricted, which can increase the risk of snoring and sleep apnea.
Sleep apnea is a medical problem marked by temporary pauses in breathing during the night. Drinking alcohol at night is a risk factor for this condition as it can create apneas even in people who are otherwise asymptomatic.
Alcohol is not the only risk factor for sleep apnea. Having anatomical features that narrow the airway, being overweight, sleeping on your back, and having a family history of sleep apnea can all increase a person’s chances of having this condition. Drinking alcohol may contribute even more to apneas in people who have co-occurring risk factors.
The health consequences of sleep apnea are significant. A primary symptom is poor sleep and excessive daytime sleepiness. Alcohol-related sleep apnea may induce numerous awakenings during the night as a result of reduced breathing and may prevent getting as much oxygen as they need to have restorative sleep.
The dangers of sleep apnea aren’t limited just to poor sleep. Sleep apnea can contribute to other health problems including risks of high blood pressure, heart attack, and stroke. It has been found to be associated with a higher risk of emotional health issues including depression. In this way, the effects of alcohol on breathing at night can affect health on multiple levels.
How Else Can Alcohol Affect Sleep?
Drinking alcohol can disturb your sleep by making you have to urinate more frequently. Obviously, drinking itself involves ingesting liquid, but the effect of alcohol on the kidneys causes them to produce more urine. As a result, drinking at night makes it more likely you’ll have to wake up to go to the bathroom.
Alcohol can cause changes in body temperature that may hinder stable sleep. At first, alcohol can help reduce your body temperature, but as the night goes on and the alcohol wears off, there can be a rebound effect that boosts your body temperature back up. For some sleepers, this may mean waking up sweaty and uncomfortable during the night.
How Does Binge Drinking Affect Sleep?
Binge drinking is defined by the National Institute on Alcohol Abuse and Alcoholism (NIAAA) according to blood alcohol content (BAC). Specifically, binge drinking is a way of drinking that causes BAC to rise to .08 or higher. For most men, this means having five or more drinks in a row, and for most women, it is four or more drinks in a row.
Many of the studies that have been conducted about alcohol and sleep focus on moderate consumption as opposed to binge drinking, but one study specifically focused on binge drinking found that it was associated with sleep disturbances.
Based on the understanding of how even moderate alcohol consumption hinders sleep, the higher alcohol concentrations from binge drinking can confer even greater risk for upsetting sleep architecture and sleep quality.
Does Alcohol Affect Sleep the Same Way For Everyone?
While research has revealed clear patterns about the way that alcohol impacts sleep, the effects will be different depending on the person. For example, men and women do not process alcohol in the same way and can experience different effects when it comes to sleep.
The way that the body and brain respond to alcohol is influenced by a person’s frequency of drinking and their tolerance. For example, some of the sedative effects of alcohol have been found to be lessened in people who frequently drink and who drink in higher quantities.
The way that alcohol is processed may depend on a person’s body weight, whether they are consuming alcohol along with caffeine, and whether they use tobacco. Diet and exercise can play a role in sleep and energy levels as well.
Sleeping problems and alcohol use can both be related to mental health issues such as depression. In some circumstances, it may be hard to know how each of these conditions influences or reinforces the other.
Sleep is a complex biological process, and alcohol can have a broad range of effects within the body. As a result, there is no simple way to say exactly how consuming alcohol will affect any given person.
That said, the science clearly indicates that, for most people, there are multiple ways in which alcohol is detrimental to getting good sleep.
Can Alcohol Be Used as a Sleep Aid?
No, it is not recommended to use alcohol as a sleep aid.
Having a drink before bed may make it seem easier to drift off to sleep. Even if alcohol makes you feel sleepy, the truth is that the quality of sleep you experience is diminished.
Furthermore, the sleep-inducing effects of alcohol are found to quickly decrease with more frequent drinking. In effect, your brain develops a certain tolerance to the sedative effects of alcohol, but the disturbances to your sleep continue, leaving you with the worst of all worlds.
Another downside of drinking to try to get to sleep is the risk of developing a dependence or other alcohol-related problem. The rapid development of a tolerance to the sedative effects of alcohol can drive people to drink more and sew the seeds of an alcohol use disorder.
What Should I Do If I’m Worried That Drinking is Affecting My Sleep?
Drinking alcohol is common across a wide range of cultures and settings. While some people can drink infrequently and with limited consequences for their sleep or health, for others, drinking can pose serious problems.
The following sections introduce information to help you know about the signs that alcohol may be affecting your sleep or other parts of your life and available resources that can help.
What Are Signs of Alcohol Misuse and Its Impact on Sleep?
More than 17 million adults in the United States have an alcohol use disorder (AUD), which makes it a relatively common condition.
Sleep problems are extremely common in people with an AUD. It is also possible to have alcohol-related sleep disruptions without having an AUD.
What Are Signs of Insufficient Sleep?
Excessive daytime sleepiness is a common sign of sleep problems. If you find that you wake up fatigued or lack energy throughout the day, it may be related to not getting enough quality sleep. The consequences of poor sleep can include irritability, reduced concentration, or otherwise worsened cognitive function.
If you can’t fall asleep when you want to, find yourself waking up multiple times throughout the night, or if you are being awoken earlier than you want, it may be an indication that you have a sleep problem. It is important not to ignore these issues especially if they are persistent or worsening.
These symptoms can be caused by issues other than alcohol. For this reason, if you have ongoing sleep problems, you should speak with a doctor who can help pinpoint the most likely cause and suggest potential treatments.
What Are Signs of a Potential Alcohol Use Disorder?
Alcohol use disorders can occur with different levels of severity and can manifest in a person’s life in a multitude of ways.
Determining whether a person has an AUD requires reflecting honestly on a range of questions about the effects that alcohol has had on a person’s life in the past year. Some of these questions include:
- Have you had times when you drank more or longer than expected?
- Have you more than once tried to stop or reduce your drinking and not been able to?
- Have you experienced strong urges to drink?
- Have you stopped doing other activities that you enjoy in order to be able to drink?
- Have you more than once engaged in risky behaviors as a result of drinking?
- Have you found the effects of alcohol to be lessened, leading you to drink more to achieve the same effects?
- Have you continued to drink even if it made you anxious, depressed, or incapable of remembering what happened while you were drinking?
- Have you experienced withdrawal symptoms if you tried to stop drinking?
Answering yes to two or more of these questions can indicate a possible AUD. The National Institute on Alcohol Abuse and Alcoholism (NIAAA) offers a free online assessment that lets you get feedback on your drinking patterns.
Alcohol use disorders can pose serious problems for health, personal relationships, and work obligations. If you have any concerns about your alcohol consumption, talk with a doctor or another medical professional who can review your situation and help connect you with the most appropriate help.
Where Can I Get Help If I’m Worried About Alcohol and Sleep?
As discussed in the previous section, your doctor is the best starting point for getting help with problems related to sleep and alcohol. Because these issues can relate to complex biological systems and processes, a well-trained doctor is in the best position to offer you advice.
What Steps Can Help Improve Sleep?
There’s no one single recipe for improving sleep, but experts agree that sleep hygiene can go a long way in boosting sleep quality.
Sleep hygiene typically focuses on your habits and your environment. Examples of improving sleep-related habits include having consistent times for going to bed and waking up, avoiding caffeine late in the day, and decreasing alcohol consumption.
Examples of improving your sleep environment could mean upgrading your mattress and pillows, using a white noise machine to reduce sound disruptions, and using blackout curtains to keep extra light out of your bedroom.
Our guide, 15 Tips for Better Sleep Hygiene, goes into more detail on ways to make it easier to fall asleep and stay asleep.
What Steps Can Help Address Alcohol Use Disorders?
Treatment can help most people who have an alcohol use disorder. There is no single approach that works for everyone, but the treatment options include behavioral therapy, various types of support groups, and medications.
Talking with a doctor is an important step in getting help if you may have a problem with alcohol. Information about treatment and suggestions for finding the best resources are available at the NIAAA’s Alcohol Treatment Navigator website.
Does Improving Sleep Help People With Alcohol Use Disorders?
Research has found that sleeping problems can increase the severity of AUDs and raise the risk of relapse for people who have stopped drinking. More research is necessary, but these findings point to the possibility that improving sleep can offer relief to people with alcohol use disorders, especially those who are in remission.
Does Ending Alcohol Consumption Improve Sleep For People With Alcohol Use Disorders?
Stopping drinking can eliminate one significant factor that can reduce sleep quality. This alone, however, does not guarantee improved sleep.
As we’ve noted throughout this article, alcohol is one of many factors that influences the amount and quality of sleep we get each night. For this reason, it is impossible to say with certainty that abstinence from drinking will improve sleep.
In addition, sleep disruptions, including changes to sleep architecture, can persist for up to 3 years after achieving sobriety. In general, the longer a person goes without drinking, the more that their sleep patterns normalize, but this can be a gradual process that can be affected by other factors, including sleep hygiene.
All things considered, many people who stop drinking will find that they have more consistent and higher-quality sleep, but it is important to know that these improvements may take time and may require attention to other issues that can influence sleep.