How Can Excessive Alcohol Consumption Affect Your Sleep?

Alcohol is widely known as a sedative, and research shows that 1 in 10 people use it to help themselves fall asleep. Once asleep, though, their sleeping patterns are disrupted.

Excess alcohol consumption before bed increases your blood alcohol levels, and your body will start to metabolize it halfway through the night. This doesn’t allow you to stay in rapid eye movement (REM) sleep or deep sleep for as long as you need to, leaving you more groggy the next morning. 

Alcohol has many adverse effects on the sleep stages, so let’s get into the different stages and their benefits, how alcohol can be causing insomnia in users, why sleep is important, and when is a good time to stop drinking before bed. 

How does alcohol affect sleep?

Sleep is an important part of a person's life with many benefits. These include the promotion of energy production of growth hormones and the lowering of risks of serious health problems. 

Some people may turn to alcohol when they are having trouble falling asleep. Alcohol is known as a sedative, but we must remember that sedation is not sleep.  

Sedation is turning off the firing of the system in the brain cells, whereas, in normal sleep that is not common, it is actually the opposite. When we are in deep sleep, our brain is still firing off these transmitters, except in a synchronized way. Alcohol also increases our fight or flight response, which will have us waking up more throughout the night. 

Not only are we waking up more through the night, but we aren’t able to reach the full potential that sleep has for us. We go through 4 stages of sleep usually through the night, and when alcohol comes into play, our bodies process it through the night which does not allow us to get the 2 most important stages of sleep.

REM Sleep vs Deep Sleep vs Light Sleep 

There are 4 stages of the sleep cycle and each one has its own importance. According to the Sleep Foundation, the stages are Non Rapid Eye Movement (NREM) NREM1, NREM2, NREM3, and REM sleep.  

NREM1 

This is the shortest stage of sleep, also known as light sleep, and can last up to 10 minutes. In this stage, a person is still easily woken up and it is usually the stage where you can see or feel them twitching. From this stage, it is easy to fall into stage 2.

NREM2 

In stage 2 a person will have a lowered heart rate, relaxed muscles, and slower breathing. This stage usually accounts for half of the night’s sleep and it will be harder for a person to wake up or be woken up by external factors. 

NREM3

Stage 3 is also known as deep sleep and is the longest stage of sleep. Here a person is much harder to wake up and the brain will begin to have a pattern of delta waves. This is arguable the most important stage in sleep, it is believed to help with body recovery, boost the immune system, and help with energy levels. 

REM

REM sleep is the last stage and the second most important stage. It doesn’t last as long as deep sleep but is considered the dream stage and is an important part of cognitive functions, including mental and emotional health.

How alcohol affects the stages of sleep

Your body will go through all four stages a few times throughout the night. Now that we understand what each of them is and their importance of them let’s see how alcohol has an effect. 

Alcohol consumption may allow you to fall asleep faster and get you into the deep sleep stage, but as you’re sleeping, your body begins to metabolize the alcohol. The second half of your sleep is actually going to be in stages 1 and 2 also known as light sleep. In these stages, you are more easily woken up, and this is what usually accounts for the groggy feeling the next day. 

In addition, this puts you out of stage 3 or deep sleep and REM sleep which accounts for all the beneficial things that come with sleep like memory, hormonal balance, and recovery. 

Alcohol and Insomnia

Let’s start out by explaining what insomnia is. According to the NIH insomnia is a common sleep disorder where someone may have difficulties falling asleep, staying asleep, or getting quality sleep. So how are these two related? Well, insomnia can naturally occur in a person, in fact, 33% to 50% of people in the US have insomnia unrelated to alcohol. When alcohol is introduced 36% to 91% of people will have insomnia, showing that alcohol dependency can cause insomnia in users. 

Benefits of a Healthier sleep cycle

Sleep is an important part of recovery for your body and for your brain. During deep sleep, Cerebrospinal Fluid flushes the brain of toxins and congestion. Clearing these toxins could help prevent neurodegenerative diseases. 

REM sleep is another very important stage in sleep and has to do with mental and emotional processing. It also plays a role in mental concentration and mood regulation according to the NSF. When not enough REM sleep is acquired throughout the night, the immune system could weaken, and the formation of new healthy cells and tissue could be blocked. 

When you get enough sleep and your sleep cycle is complete and on a regulated schedule, the body has enough time to recover from daily stresses. You are allowing it to recover completely, not just from being tired, but more physiological effects are happening that you may not have even known about. 

How many hours before bed should I have my last drink?

Research shows that having a final drink 3 to 4 hours before bed would be best if you needed to drink that late at night. Alcohol takes approximately 1 hour to process in the body and that is for a single serving, so if you are taking more servings at a time your body will take longer to process it. 

Final Thoughts

Sleep is important, and I don’t think you needed me here to tell you the importance of sleep, but I am here to explain the negative effects that alcohol can have on your sleep. Allowing your body enough sleep is good for your health, mental state, emotional state, and overall well-being. 

When you cut back on drinking, you will hit 5-6 more REM cycles, which will help you retain more emotional and mental information as well as get through all of the sleep stages fully and allow them to cycle correctly. Decreasing your alcohol consumption before bed will help increase your sleeping patterns throughout the night and not leave you feeling more tired or groggy the next morning.