Whether you love a glass of wine, a frosty mug of beer, or a mixologist-made cocktail, you know that one side effect of alcohol is feeling sleepy. “Alcohol is a central nervous system depressant so it slows the system and leads to sedation,” explains Fitbit Sleep Advisor Allison T. Siebern, PhD, consulting assistant professor at Stanford University Sleep Medicine Center and director of the Sleep Health Integrative Program at the Fayetteville VA Medical Center in North Carolina.
Although this sounds like it could be ideal—enjoy a cocktail and fall asleep quickly!—it is a limited benefit. “Many people use alcohol to get to sleep. In fact, alcohol is probably the most widely-used sleep drug in the world,” explains Michael Grandner, PhD, MTR, director of the Sleep and Health Research Program at the University of Arizona College of Medicine. “But the relationship between alcohol and sleep is complex and somewhat counterintuitive.”
Here, the facts about sipping alcohol and snoozing.
Alcohol May be Good Now; Bad Later
Yes, a nightcap may help you drift off to dreamland faster and it can even help you sleep more deeply in the first part of the night. (One exception is if you have a drinking problem as these benefits tend to disappear and alcohol can actually cause insomnia.) However, pre-bed cocktails can also suppress one of the most restorative stages of sleep called REM, which is where dreaming takes place. Disruptions in this stage, which occurs about 90 minutes after you fall asleep, can leave you feeling drowsy in the A.M. and, as a result, less productive and able to concentrate. In fact, alcohol can lead to increased nightmares in this stage, cautions Siebern. Lastly, if you are drinking to help you fall asleep, you increase your chances of being dependent on pre-bed cocktails.
Alcohol Needs Time to Make its Exit
It’s stressful work for your body to clear alcohol out of its system and this can make your sleep less restful. “As the alcohol is broken down, it can cause changes in your body and brain that can actually serve to wake you up,” explains Grandner. This is why, after a night of heavy drinking, many people are wide-eyed a few hours after they hit the sack and cannot get back to sleep. “It takes about one hour per serving of alcohol to clear out of your system,” explains Grandner. A general rule of thumb is to stop sipping about three hours before bed.
You May Lose More Than Sleep
Toasting with a few nightcaps can lead to increased urine production, dehydration and breathing disruption, explains Siebern. Though a few bathroom trips and feeling thirsty aren’t a big deal, breathing issues are. In fact, cocktail consumption may bring sleep apnea on more quickly than usual. This is a serious condition where your breathing is disrupted or briefly comes to a stop while you snooze, decreasing the amount of oxygen flowing to your brain and body. In turn, this ups your risk of serious health issues like hypertension stroke or heart failure.
This article is not intended to substitute for informed medical advice. You should not use this information to diagnose or treat a health problem or condition. Always check with your doctor before changing your diet, altering your sleep habits, taking supplements, or starting a new fitness routine.