Have you ever spent an evening imbibing a little too much and then felt completely exhausted the next day? Yes, you probably stayed up later than you’re accustomed too. You’re also dehydrated and probably feeling hung over, but the tiredness you’re feeling also has a lot to do with the effect alcohol has on your sleep.
If you drink too much, you may feel like you get to sleep easily, but falling asleep and getting restorative sleep are two different stories. Sure, you may fall asleep quickly, but alcohol can keep your body from going through all the necessary sleep cycles.
The problems alcohol can cause your sleep aren’t just limited to people who drink too much. About 20% of Americans say they use alcohol as a sleep aid. That nightly glass of wine you think helps you sleep? Well, it turns out it’s probably doing more harm than good.
Alcohol and REM Sleep
In the short term, alcohol can help people fall asleep faster. Studies have shown that, in healthy, non-dependent people, alcohol can decrease the time it takes to fall asleep. However, it’s been found drinking alcohol can reduce the amount of time people spend in REM sleep, an essential part of cellular restoration and brain function.
The most healthy, restorative sleep is done when your natural sleep cycles are allowed to occur as they should. When you drink, however, the body can skip REM sleep in the beginning half of the night and go right into deep sleep
Without the proper amount of REM sleep, the next day can leave you feeling pretty fuzzy. Your memory and concentration skills will probably feel out of whack.
When alcohol is metabolized during the second half of the night, it again disrupts the usual cycle. The second half of the night is when your body should be in slow-wave, or deep sleep. As the alcohol dissipates, so does its sedative effect. Your brain can then “rebound” and move to the lighter REM sleep. It’s much easier for your body to get awoken from REM sleep than deep sleep.
If you’re someone who wakes up early or can’t get back to sleep in the middle of the night, alcohol use may be to blame.
Sleep Hormones and Your Heart
Alcohol can also affect how your body normally produces sleep hormones. When you’re drinking, your brain produces more adenosine at a fast rate, which makes you feel sleepy quickly. Once you’re asleep, however, your brain stops producing that hormone, making you more likely to wake up in the middle of the night or early in the morning.
Scientists have also found that alcohol impacts your HRV (heart rate variability). In order to get into a restorative state of sleep, your heart rate needs to beat slower. If you drink alcohol, your heart rate doesn’t slow as much as it should. If your heart rate is even slightly elevated as you sleep, you’ll be less recovered the next day.
We all know alcohol can help you relax, but being too relaxed while you sleep can be problematic. If the muscles in your throat are too relaxed, you can be more prone to snoring and sleep apnea—neither of which are beneficial to a good night’s sleep.
All these issues are compounded the more you drink.
Protect Your Circadian Rhythm
An essential part of your healthy, natural sleep cycle is your circadian rhythm. This clock regulates many functions in the body, including the quality of your sleep. When you’re constantly up too late or awake in the middle of the night, this rhythm gets off.
A disrupted sleep-wake cycle can cause depression and anxiety. It can also cause your liver to function abnormally, and can even be the cause of weight gain.
Don’t worry, we’re not telling you that you have to quit drinking alcohol entirely. We do think, though, it’s important for your overall health and wellbeing that you don’t use alcohol as a sleep aid and that you don’t over-imbibe more than a couple times per year.
Remember, even one drink can alter the way your body sleeps. So, take care of yourself and be smart about when and how much you drink.