The term “nightcap” is a popular expression for having an alcoholic beverage before sleep, and many people swear by a glass of wine or a cocktail to help them relax and send them off to dreamland. However, alcohol may have a negative effect on sleep and can, over time, significantly disrupt your sleep hygiene, leading to a host of other health problems and sleep disorders.

Results of surveys show 15-28% of Americans use alcohol to help them fall asleep. However, even regular, moderate drinking can affect your circadian rhythms and your body’s natural sleep-wake cycle.

You most likely don’t need to quit drinking altogether, but responsible alcohol consumption can help you avoid some of the effects that alcohol has on healthy sleep.

Alcohol and Its Sedative Effect

Alcohol may make some people more energetic, but it’s actually a depressive substance, not an “upper.” The sedative effects of alcohol may be why it’s a popular sleep aid, but regular use of alcohol in this manner can result in alcohol dependence. While drinking alcohol may reduce the time it takes to fall asleep, as the alcohol wears off, you might have more disrupted sleep during the second half of the night.

The sedation from alcohol can also lengthen periods of sleep apnea in diagnosed individuals. Even people with no prior symptoms of sleep apnea can experience episodes after consuming alcohol before bedtime.

Many people believe that drinking before bed helps them sleep, but it’s not as restorative as they think. In fact, alcohol disrupts your internal clock, the circadian rhythms that cover everything from sleeping and eating to appetite and even your sex drive and cognitive abilities. With the disruption to your circadian rhythm, your alertness, appetite and ability to focus are compromised.

REM Sleep and Drinking Alcohol

While falling asleep after drinking alcohol may seem easier, as the body processes alcohol, it affects the body’s capability to have a full, complete sleep cycle. This includes interruption and shortening of the REM sleep cycle, or Rapid Eye Movement — the part of sleep when you dream.

Alcohol Before Sleep Affects the Whole Body

REM sleep isn’t the only thing that alcohol inhibits during shut-eye. Many people may experience sleepwalking or sleep talking and have trouble with their memory. Interrupted sleep contributes to memory loss and the ability of your brain to convert short-term memories into long-term ones. Over time, memory loss increases and can even lead to early-onset dementia or Alzheimer’s disease.

Alcohol has other effects on different systems of the body, which depend on the restorative effects of a good night’s sleep to heal and prepare for the next day. Regular consumption of alcohol before bedtime can also lead to:

• Reduced liver function: Your liver is the body’s filtration system and metabolizes food and other chemicals, including alcohol, and removes toxins from your body and bloodstream. Drinking alcohol before bedtime interferes with your liver’s ability to remove these toxins from the body and can lead to liver toxicity and other liver diseases, such as cirrhosis.
• Leaky gut: This refers to a weakening of the gastrointestinal tract, making it thinner and more vulnerable to perforations (holes) that can cause sepsis, a deadly infectious condition. The circadian rhythms operate the gut and control the biome within — the bacteria that make their home and serve as your body’s “second brain.”
• Clinical depression: Lack of sleep and alcohol dependence may lead to clinical depression, although some believe it works the other way, as well, with depression leading to poor sleep habits and alcohol dependence. The presence of moderate amounts of alcohol in the body can impact your body’s natural rhythms and brain chemistry, worsening the condition.
• Disrupted sleeping cycles: Excessive use of alcohol actually suppresses your body’s ability to produce melatonin, the hormone that promotes sleep. Even a moderate amount of alcohol before bedtime can reduce your melatonin production by up to 20%. Without this naturally occurring chemical, it’s harder to fall asleep, making many people depend on alcohol for the sedative effect that melatonin normally provides.

Finally, alcohol interferes with your body’s internal sleep drive. Alcohol increases the levels of adenosine, which is a hormone that regulates your sleep cycle. It increases gradually the longer you’re awake, but alcohol can block this and other chemicals that help you naturally wake and sleep. Reducing adenosine can make you sleep at times that you ordinarily wouldn’t and disrupt your sleep-wake cycle.

Better Habits for Better Sleep

Instead of having a nightcap or two before bedtime, choose other healthy sleep habits that help you fall asleep more peacefully, have the restorative REM sleep you need and wake to feel refreshed. Here are a few strategies to help you get better sleep.

• Incorporate regular exercise into your daily routine — but take care not to work out within a few hours of bedtime.
• Avoid alcohol, nicotine and caffeine in the evening.
• Make sure that you reserve your bed for sleeping and sex only — don’t work or eat in bed. This helps retrain your brain to associate being in bed with sleep.
• Maintain a cool temperature in the bedroom, using a fan if needed.
• Stick to a regular sleeping and waking schedule, even on weekends.

When to Talk to a Doctor

If you find that you can’t fall asleep without having alcohol, or if alcohol use is beginning to affect your daily life, you should speak with a doctor or sleep specialist. These specialists can also help you rule out other underlying sleep disorders such as sleep apnea and can help you with different sleep aids. Depending on alcohol — or anything else — for sleep can have destructive effects on your health and relationships.

Good sleep starts with good habits, and while the occasional adult beverage can help you when sleep just won’t come, making alcohol a part of your daily bedtime sleep ritual can be unhealthy.

The benefits of a good night’s sleep cannot be overstated. A good night’s sleep can improve your work performance, give you more energy and make your relationships more positive. Good sleep can also improve your fitness level and may even aid weight-loss goals.