How Alcohol Affects REM Sleep & Sleep Quality
When you’re wound up in the evening after a long tiresome day, a nightcap might sound like the best way to relax before bed. After all, sleepiness and relaxation are common and welcomed side effects of drinking alcohol. A few drinks appear to bring relief, especially for individuals struggling with sleep disorders. Around 20 – 30% of patients with insomnia often rely on alcohol to help them fall asleep faster.
But don’t be fooled. While a little alcohol might make you feel sleepy and drift off faster at night, it can alter the total sleep time, disrupt the duration and structure of sleep states, and affect the time needed to fall asleep. Plus, people who take late-night drinks often wake up tired in the morning.
So, does this mean you should avoid drinking alcohol altogether, or is a harmonious relationship between alcohol and sleep possible?
Read on to learn more about the connection between alcohol and sleep.
Alcohol and Sleep: How a Normal Night of Sleep Looks Like
Generally, human beings have a sleep cycle that travels from non-rapid eye movement sleep (non-REM sleep) to REM sleep. Non-REM sleep is composed of three different sleep stages. The higher the stage, the harder it is to wake you from your slumber.
This is essentially the dozing-off period (lighter state of sleep), and it usually lasts for about one to five minutes. Here, the body hasn’t fully relaxed, but brain and body activities start to slow with short periods of twitches (brief movements).
The body moves into a more subdued state, including relaxed muscles, a drop in temperature, and slowed heart rate and breathing. Eye movements stop, and brain waves show a new pattern. This stage can last for about 10-25 minutes during the first cycle and can become longer during the night.
Also known as delta sleep, slow-wave sleep (SWS), or deep sleep, this is the stage where pulse, muscle tone, and breathing rate decrease as your body relaxes even further. Sleep experts believe that this sleep stage is crucial to restorative sleep, allowing bodily growth and recovery.
Stage 4/ REM Sleep
During this stage, brain activities pick up. At the same time, your body experiences temporary paralysis of your muscles (atonia) with two exceptions: your eyes and the body muscles that manage breathing. Under normal circumstances, sleepers don’t enter the REM sleep period until they sleep for about 90 minutes.
How Does Alcohol Affect Sleep?
Alcohol suppresses the central nervous system, which affects sleep in various ways. As a sedative, alcohol may initially assist you in getting to sleep on time, but overall, it may exacerbate certain sleep problems, disturb the sleep cycle, and consequently create repercussions during waking periods. Various studies looking at how alcohol affects sleep show that alcohol:
- Minimizes the time needed to sleep (sleep onset latency)
- Increases the amount of deep sleep
- Minimizes the amount of REM sleep
Prolonged drinking can also lead to tolerance of the effects of alcohol. For instance, research has it that within three days of consistent drinking, individuals develop a tolerance to the sedative effects of alcohol.
Consuming an excessive amount of alcohol within a short period (binge-drinking) can be particularly harmful to your sleep health. Studies show that individuals who engage in weekly binge drinking are more likely to take a nap during the day and have trouble falling asleep at night.
How Alcohol Affects Different Sleep Stages
Non-REM Sleep (NREM Sleep)
During the first few hours of the night, alcohol significantly increases the amount of NREM sleep, irrespective of the amount consumed. However, as you progress through your sleep, the effect of alcohol on NREM sleep depends on the amount of alcohol you take. No clear trend has been seen among light drinkers, but moderate to high drinkers tend to have an increased non-REM sleep. It's worth noting that alcohol consumption has a different impact on teenagers.
There’s a well-established connection between reduced REM sleep and alcohol. Drinking lightly (less than two drinks) or moderately doesn’t affect REM sleep during the first period of the night. On the other hand, individuals who drink heavily tend to experience a significant reduction in REM sleep during the same nightly sleep period.
When the entire sleep cycle is considered, moderate and heavy drinking minimizes the total REM sleep percentage. This negative effect isn’t observed among those who drink lightly, making researchers conclude that a decrease in REM sleep is directly linked to the amount of alcohol consumed.
Alcohol and Sleep Disorders
Alcohol consumption at almost any level causes sleep disturbances, impacts your circadian rhythm, and can induce sleep disorders. For instance, studies have found that chronic alcohol use can increase sleep apnea symptoms, especially among sleepers who snore.
Here’s how drinking alcohol exacerbates certain sleep dysfunctions:
Insomnia is the most common sleep disorder, affecting about 25% of Americans each year. It may include the following symptoms:
- Persistent difficulty with sleep initiation
- Waking frequently during the night
- Persistent difficulty with sleep consolidation
- Waking too early
- Daytime sleepiness
Since alcohol can cause sleep disturbances and reduce REM sleep, you might experience insomnia symptoms and excessive daytime sleepiness if you drink before bed. This can lead you into a vicious cycle, consisting of self-meditating with alcohol to help you fall asleep faster, taking stimulants to stay awake during the day, and then using alcoholic drinks as sedatives to counteract the effects of these stimulants.
Obstructive Sleep Apnea (OSA)
Obstructive sleep apnea is a dysfunction characterized by temporary loss of breath and frequent pauses in breathing during sleep. These lapses in breathing often last 10 to 30 seconds and may happen several times during the night, causing sleep disruptions and decreased sleep quality.
Often, OSA occurs due to physical blockage when the soft tissues at the back of your throat collapse, closing the airway. Central sleep apnea (CSA), on the other hand, happens when your brain can’t properly signal the body muscles that control breathing. A narrow respiratory tract, relaxed throat muscles, and a large tongue can also block the airway.
You may make choking noises during apnea-related breathing episodes. People suffering from sleep apnea are also susceptible to loud, disrupting snoring. If you drink alcohol, you can disrupt breathing during the night by relaxing your throat muscles. It can also reduce your brain’s ability to detect a lack of oxygen in your body, leading to longer and more frequent pauses. That’s why it’s recommended that patients with sleep apnea either cut back on their drinking or avoid drinking altogether.
Can You Sleep Better After Drinking Alcohol?
Drinking alcohol before bed can greatly interfere with your sleeping pattern and affect sleep quality. However, if you just can't sleep without drinking, there are healthy sleep tips that can help you manage your consumption for better sleep.
Have a Balanced Meal
Drinking your favorite beer on a full stomach can significantly reduce the impact of alcoholic drinks on your sleep. So, when you're sipping some spirits at home or going out for a drink, make sure you take dinner first. A solid, balanced meal can help regulate your body system's absorption of the alcohol, minimizing its overall impact on your body.
For a good night's sleep after drinking, it's wise to refrain from consuming caffeinated drinks like coffee, energy drinks, and sodas as they can further affect your sleep pattern and quality. This will make it much harder for you to enjoy a restful sleep. So, avoid caffeinated drinks, especially 3 - 4 hours before you hit the sack.
Don't Use Alcohol as a Sleep Aid
While we all have tricks that help us fall asleep quickly, using alcohol isn't a healthy way of getting restorative sleep. So if you often have trouble sleeping and staying asleep, consider swapping out taking alcohol for relaxing activities like reading a book, taking a bath, or even doing yoga. It can be any activity that helps you wind down.
Regular, uninterrupted sleep is vital for your health and well-being. If you're looking for a night of restorative sleep, work on developing healthy sleep habits instead of reaching for alcoholic drinks. However, if you've stopped drinking but still have trouble sleeping and maintaining sleep, consider reaching out to a sleep specialist.