About 20% of adults in America use alcohol to help them sleep faster. But new research shows that the beverage can actually have a bad effect on how we sleep and may cause insomnia over time.

According to the researchers from the University of Missouri School of Medicine, alcohol does induce sleep, but it does so by changing how our circadian rhythm works. Circadian rhythm is the body’s natural clock as it dictates when it’s time to sleep and when it’s time to wake up.

But What’s the Problem?

Alcohol does help with sleep, but at the same time, it affects sleep homeostasis, which is the natural mechanism in the brain that controls being sleepy and being alert. This mechanism is how our body balances our requirement for sleep based on the amount of time we’ve been awake by using a chemical found in the cells known as adenosine. When were awake for a long period of time, levels of adenosine increase then go down when we’re sleeping. So if you’re sleeping earlier than normal, you could wake up very early in the morning or you keep waking up in the middle of the night.

In Short, Alcohol Doesn’t Give You Enough REM Sleep

British researchers reviewed over 150 studies associated with alcohol and sleep. They found that drinking at least four beers before going to bed can disrupt the sleep cycle. As a result, you have fewer dreams because you’re awake most of the time and your heart rate is elevated as well. Rapid Eye Movement or REM is when we dream and the brain needs this type of sleep to prepare itself for the next day.

Drinking and sleeping may be as bad as drinking and driving.
Drinking and sleeping may be as bad as drinking and driving.

Timeline of Alcohol’s Effects on Sleep

Here’s what happens if you turn to alcohol to help you sleep:

#1: You fall asleep faster, thanks to alcohol.

But you have a depressed brain and soon, you enter a deep sleep before you’re supposed to. Heart rate is elevated, causing some parts of your nervous system to be more active.

#2: You’re sleeping deeply, but the rest of your body is active.

You’re also not dreaming and your body is not moving.

#3: You sleep like a baby.

But you wake up groggy in the morning because you experienced 9% less REM sleep.

#4: As the effects of alcohol wear off, the part of your nervous system that did not shut down starts to kick in.

The sympathetic nervous system will start waking you up.

#5: Your body is restless now as you keep waking up – even without knowing it.

With the alcohol almost completely metabolized, you spend most of the night awake.

Because your sympathetic nervous system keeps you active, you can no longer fight the urge to get up. You didn’t get enough sleep and you’re not ready for the next day. That’s what alcohol does to your supposed-to-be peaceful slumber.