Think A Nightcap Is Good For Your Sleep? Think Again

A nightcap looks like an easy and efficient option to help you fall asleep faster at night. After all, consumption of alcohol does make you sleepy. Recent studies, however, point the other way. They show alcohol can negatively impact sleep patterns.

The popularity of alcohol as a sleep aid can be attributed to its sedative effects. It acts as a central nervous system depressant, meaning alcohol slows down brain activity. Yet, this initial drowsiness is offset by restless sleep later into the night.

"Unfortunately, alcohol never improves sleep. Although alcohol helps you relax, making falling asleep easier for some, three to four hours after falling asleep, people wake up and can't get back to sleep. Conversely, people dependent on alcohol can't fall asleep if they don't drink," said Dr. John Mendelson, founder of Ria Health and a clinical professor of medicine at the University of California, San Francisco.

There are four stages of sleep. The first three stages are non-Rapid eye movement (REM) phases and the last one is the REM phase. Alcohol use disrupts the sleep cycle, particularly the REM stage, which is the dreaming phase.

"Evidence now suggests the deeper sleep of alcohol is also associated with an increase in frontal alpha waves, markers of wakefulness, and sleep disruption. Thus the deep sleep of alcohol is likely not to be restorative," said Dan Ford, a sleep psychologist from Auckland, New Zealand.

In other words, the quality of sleep is affected by alcohol consumption. The benefits of the REM stage are lost in alcohol-induced sleep. As a result, you may end up feeling tired, which can influence your performance the next day.

Another way nightcap can affect sleep is by decreasing melatonin production. Melatonin is a hormone released from pineal glands that control the circadian rhythm of our body. It is produced in the skin through sun exposure and can help induce sleep. A new study found that drinking alcohol before going to bed reduced melatonin production by 20%.

Alcohol, when used as a sleep aid, can also amplify sleeping disorders like obstructive sleep apnea (OSA). Since it acts as a muscle relaxant, alcohol consumption can lead to a situation in which soft tissues in the throat collapse and block the upper airway, causing difficulty in breathing and even temporary loss of breath. Studies have found that alcohol consumption increases the risk of sleep apnea by 25%.

In individuals with OSA or those who typically snore, alcohol can increase the severity of snoring and lower oxygen levels, especially when they drink close to bedtime, doctors say.

Even a small amount of alcohol can affect sleep patterns, so it is better to give the nightcap a miss before going to bed. If you still feel the need to drink liquor at night, take it four hours before going to bed.

"If you choose to drink alcohol, drink in moderation and stop at least four hours before bedtime to avoid its negative effects on healthy sleep," said Dr. Raj Dasgupta, an assistant professor of clinical medicine at Keck School of Medicine at the University of Southern California.