Alcohol And Sleep: A Troubled Relationship

Alcohol has a complicated relationship with sleep. While it can make you feel drowsy, it can also disrupt your sleep, leaving you feeling tired the next day. Research shows that alcohol can reduce sleep quality over time, causing issues such as insomnia and snoring, and increasing the risk of sleep disorders. Alcohol can also cause a bidirectional relationship with sleep, where those who drink often experience disrupted sleep, and those who find it difficult to sleep well may use alcohol as a coping mechanism.

Alcohol can be stimulating and reduce melatonin, making it harder to fall asleep

Alcohol can be stimulating, especially in low doses, and this can make it harder to fall asleep. This is one of alcohol's biphasic effects—it can be stimulating and sedating at different times.

Alcohol can also reduce melatonin, the hormone that primes your body for sleep. A study found that melatonin levels were reduced by 15% two hours and 20 minutes after moderate alcohol intake, and by 19% three hours and 10 minutes after. As your body metabolises the alcohol and the sedative effects wear off, it can interfere with your circadian rhythm, causing you to wake up frequently or before you're properly rested.

Alcohol can also cause or worsen anxiety, which may leave you wide awake in bed. It could also trigger a vicious cycle, as sleep loss makes anxiety worse, which may cause you to self-medicate with more alcohol to try to relax.

Alcohol can cause or worsen anxiety and sleep disorders

Alcohol can also reduce the production of melatonin, the hormone that primes your body for sleep. A study found that melatonin levels were reduced by 15% two hours and 20 minutes after moderate alcohol intake and by 19% three hours and 10 minutes after alcohol consumption.

Additionally, alcohol can trigger or worsen anxiety. It is a depressant that slows down processes in your brain and central nervous system. While it can make you feel less inhibited and more relaxed initially, these effects are short-lived. As the effects of alcohol wear off, you may experience increased anxiety as your body goes into 'fight or flight' mode. This can lead to a vicious cycle where you drink more alcohol to relieve anxiety, only to have the anxiety worsen as the alcohol leaves your system.

Furthermore, alcohol can disrupt your sleep by interfering with your circadian rhythm. It can decrease your body's sensitivity to cues like daylight and darkness, which are essential for regulating your sleep-wake cycle. As a result, you may feel alert when you want to sleep and sleepy when you want to be awake.

If you are experiencing sleep disturbances due to alcohol consumption, it is recommended to avoid alcohol at least three to four hours before bedtime. Improving your sleep hygiene, such as avoiding bright lights and creating a cool bedroom environment, can also help you sleep better.

Alcohol can fragment your sleep, causing more nighttime awakenings

Alcohol can have a detrimental impact on sleep quality. While a drink or two may help you fall asleep faster, it is likely to disrupt your sleep later in the night.

Alcohol is a central nervous system depressant. It may make you sleepy initially, but the sedative effects can wear off in the second half of the night, causing more nighttime awakenings. This is one reason why you might find yourself waking up in the middle of the night after drinking.

Alcohol can also cause sleep fragmentation by disrupting your sleep architecture, or how your body cycles through the four stages of sleep. The typical sleep cycle consists of three non-rapid eye movement (NREM) stages and ends with rapid eye movement (REM) sleep. During sleep, the body cycles through all these stages every 90 to 120 minutes, with NREM sleep dominating the first part of the night and REM sleep increasing in the latter half.

When you go to bed with alcohol in your system, you are likely to experience more N3 sleep, or "deep sleep," and less REM sleep than usual. Later in the night, once your body has metabolized the alcohol, you are likely to experience a rise in N1 sleep, the lightest stage of sleep. This can lead to frequent awakenings and fragmented, low-quality sleep.

Research has found that drinking alcohol six hours before bed doubles wakefulness in the second half of the night. Alcohol can also cause or worsen sleep disorders such as insomnia and sleep apnea. It can increase your risk of sleep apnea by 25%, as it relaxes the muscles in your throat and makes it easier for your airways to close and cut off your breathing while you sleep.

Additionally, alcohol can trigger night sweats, dehydration, and the need to use the bathroom more frequently during the night, further disrupting your sleep.

Alcohol can cause dehydration and frequent urination, disrupting sleep

Alcohol can be dehydrating, and it also has a diuretic effect, which means you may wake up during the night needing to use the bathroom. This can disrupt your sleep, and you may find yourself getting up several times.

Alcohol is a diuretic, which means it increases the amount of water and salt that is expelled from the body. This can lead to dehydration, and frequent urination. As a result, you may find yourself waking up multiple times in the night to use the bathroom, disrupting your sleep.

Alcohol can also affect your body's ability to rehydrate, which is essential for your body to recover during sleep. Dehydration can cause sleep disruption, and you may wake up feeling tired and groggy, even if you have had a full night's sleep.

To reduce the impact of alcohol-induced dehydration and frequent urination on your sleep, it is recommended to stay well-hydrated throughout the day, especially if you know you will be drinking alcohol in the evening. It is also a good idea to avoid drinking too much water right before bed, as this can increase the likelihood of needing to use the bathroom during the night.

In addition to causing dehydration and frequent urination, alcohol can also affect your sleep in other ways. It can interfere with your body's production of melatonin, the hormone that primes your body for sleep. Alcohol can also disrupt your sleep cycle, reducing the amount of REM sleep you get, which is the deepest stage of sleep associated with restorative sleep and dreaming.

Overall, while a glass or two of alcohol may help you fall asleep faster, it is likely to disrupt your sleep later in the night and reduce your overall sleep quality.

Alcohol can trigger sleep disorders such as sleep apnea, sleepwalking, and insomnia

Alcohol can have a detrimental impact on sleep quality and duration, and it is linked to various sleep disorders. Alcohol use disorder (AUD) is associated with a higher risk of sleep disorders, and over 70% of people with AUD experience sleep issues such as insomnia.

Sleep Apnea

Alcohol can trigger sleep apnea, a disorder characterised by interrupted breathing during sleep, resulting in snoring, gasping, choking, or snorting sounds. Drinking alcohol relaxes the muscles in the airway, causing obstructions that lead to sleep apnea. Alcohol also increases the time between when a person stops breathing and when they "wake up" to breathe again, intensifying the severity of the condition.

Sleepwalking

While there is no direct experimental evidence, alcohol is believed to be a trigger for sleepwalking. It is thought that alcohol increases the risk of sleepwalking by increasing the quantity of slow-wave sleep (SWS). However, some studies on healthy non-drinkers and social drinkers found no change in SWS, while studies on alcohol abusers showed a reduction or absence of SWS.

Insomnia

Alcohol is linked to insomnia, causing difficulty falling asleep, staying asleep, or waking up too early. Even moderate amounts of alcohol are associated with decreased REM sleep duration, longer wake times after falling asleep, and a longer time to fall asleep. Research shows that heavy drinkers have a 64% greater risk of insomnia, while less frequent binge drinkers are 35% more likely to develop insomnia than non-drinkers.

In summary, alcohol can trigger and exacerbate sleep disorders such as sleep apnea, sleepwalking, and insomnia, leading to disrupted sleep patterns and reduced sleep quality.

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