A Comprehensive Look at How Alcohol Affects Your Sleep

Drinking beer, wine, or liquor can make you feel drowsy and help you drift off into a peaceful night of rest. But is the alcohol improving or disrupting your sleep? 

It seems so simple – just fall asleep. But many Americans struggle with falling asleep each night. In fact, almost 20% of Americans use alcohol as a sleep aid. 

Before you do, consider there are several factors that contribute to our sleep being less than ideal when consuming alcohol. Alcohol can disturb our circadian rhythms, interfere with our natural sleep regulators, create a battle between our alpha and delta brain waves, and block much-needed REM.  On top of this, alcohol increases our need to urinate in the middle of the night and aggravates breathing problems which interrupt our sleep even further. 

Read on for details and also learn how using BACtrack when you drink can have an enormous impact on your sleep quality.

Alcohol Before Bed Disturbs Circadian Rhythms

While the body metabolizes alcohol differently at various times of the day, the effects on sleep are evident. A comprehensive review of recently published studies all had similar outcomes surrounding the investigations of alcohol’s effects on sleep: it reduces the time it takes to fall asleep, increases the amount of deep sleep during the first half of the night, promotes sleep disturbances in the second half of the night, and should never be used to treat insomnia. Additionally, in a 2011 study, researchers found the effects of alcohol on sleep disturbances are more acute for women than men.

Inside our brain is a small part called the hypothalamus that houses a master biological clock called the suprachiasmatic nucleus (SCN). This biological clock coordinates circadian rhythm activity throughout the body which includes sleep, metabolism, sexual drive, cognitive function, and mood.

Alcohol directly disrupts these activities by not allowing the clock to synchronize itself. It also suppresses the production of melatonin which plays a huge role in the regulation of sleep-wake cycles. Alcohol also reduces the body’s ability to respond to light cues which help it stay in sync throughout the day. 

Alcohol Interferes with Our Natural Sleep Regulators

Ultimately, not all sleep is created equal. In fact, researchers found that alcohol-induced sleep interferes with the body’s natural sleep regulation system.  Alcohol artificially depresses the central nervous system, relaxes your muscles, and reduces the activity in parts of your brain which all lead to a drowsy feeling and ultimately sleep. But it is not a natural way to fall asleep, so the quality of sleep is diminished. 

Falling asleep quickly after drinking is due in part to the increased production of adenosine in your body which is a sleep-inducing chemical in the brain. Throughout the day, adenosine levels slowly rise in relation to how long you have been awake. Increased adenosine helps you fall asleep quickly, but extra adenosine caused by alcohol consumption depletes quickly so you wake up in the middle of the night. Often times, your body will wake up before you are truly rested as the adenosine subsides. This extra dose of adenosine from alcohol throws off your natural sleep-wake cycle.

Alcohol is a Diuretic

Waking up in the middle of the night to use the bathroom always interrupts sleep. The interruption could be quick and you fall instantly back asleep or you could lie awake for quite a while before drifting back off.  Either way, it disrupts our sleep. Alcohol is a diuretic which means that it increases the excretion of urine.  Alcohol reduces the production of the hormone vasopressin.  Reduced levels of vasopressin cause the kidneys to send water directly to the bladder instead of reabsorbing it into the body.  Alcohol reduces the vasopressin so your bladder fills up with fluid faster than it would normally. No wonder you have to go to the bathroom so often! 

The Battle Between Alpha and Delta Brainwaves

Drinking alcohol before bedtime produces both alpha and delta waves in the brain. Delta brainwaves allow for memory formation and learning during a deep sleep. Alpha waves generally don’t occur during sleep, but rather when you are awake or quietly resting. Researchers found that when activated together because of drinking, the alpha and delta activity in the brain can prevent restorative sleep.

Alcohol Reduces REM Sleep

Alcohol is linked to lower-quality sleep because it reduces REM sleep especially during the first part of the night.  REM sleep is the most restorative type of sleep. But the first REM sleep period is significantly diminished when consuming alcohol, regardless of the amount.  With less total REM sleep throughout the night, you’re likely to wake up feeling tired, slow, and a bit fuzzy.

Alcohol Aggravates Breathing Problems

Drinking alcohol causes your whole body to relax and this includes all the muscles in your throat which can lead to more frequent and increased duration of breathing problems during sleep. When your throat muscles relax due to drinking, it makes you more prone to snoring and sleep apnea. According to the National Sleep Foundation, more than 18 million adults have sleep apnea, a condition in which breathing is interrupted during sleep. Consuming alcohol can result in increased and more frequent breathing difficulties. 

Using a BACtrack to Improve Your Sleep

While everyone knows a BACtrack is an essential safety device, it can also be used to help improve your sleep. Here are just a few ways:

1. Use a BACtrack to understand how alcohol affects your body and the impact a given BAC level has upon your sleep quality. The more you use your BACtrack when you drink, the better you'll understand alcohol's effects.

2. With the BACtrack app's Zeroline® feature, you can learn when all of the alcohol will be out of your system once you stop drinking; the app will give you the estimated time to return to 0.00%BAC. It’s interesting to see just how long it takes with a standard alcohol elimination rate of .015% BAC per hour.

3. Shown in the image above, the BACtrack app can optionally save your past BAC results. This tracking feature makes it easy for you to review past results and examine any correlation between your BAC level and testing time relative to your sleep quality.

4. Connect your BACtrack app to Apple's Health app to graph your BAC level (shown below) and your sleep quality (another toggle in the Apple Health app). Viewing these two graphs simultaneously gives you a quick visual of how your BAC level may (or may not) impact your sleep.

Find a BACtrack

To access the BACtrack app, choose a model with smartphone connectivity, our BACtrack Mobile or BACtrack C6. Of course, you can still track your BAC with other models, like our best-selling BACtrack S80.

Learn for yourself how awareness about your BAC level when you're drinking can have an enormous impact on your sleep quality!