Given that the term ‘nightcap’ typically refers to an alcoholic tipple, it’s easy to assume that alcohol is a good sleep aid. While it can make us feel more sleepy, and often help us get to sleep more quickly, in fact, it’s more likely to induce poor and disturbed sleep quality, and thus make us more tired the next day.
How does alcohol affect sleep?
Alcohol is a depressant, which suppresses the central nervous system, and causes the brain activity to slow down. All types of alcohol - beer, wine, cocktails, liqueurs, and spirits - have this effect. In large quantities, alcohol makes us feel relaxed and dozy, with a sedative effect that makes going to sleep more akin to passing out.
When we consume alcohol, it gets absorbed into our blood stream through the stomach and small intestine. Liver enzymes metabolise the alcohol, however, as this is a slow filtration process, if we have consumed a lot, it can mean that we have high levels circulating in our blood stream for some hours.
Alcohol can suppress Rapid Eye Movement during the first two sleep cycles, which can create an imbalance of slow wave sleep and REM sleep, which in turn creates shorter sleep duration and more sleep disruptions.
A hangover is often a combination of dehydration and sleep deprivation, so we may also wake during the night needing to urinate, rehydrate, take painkillers, or from feeling too hot or nauseous. In addition, those who are prone to snoring can usually testify that the problem is worse after they have had a drink.
Alcohol and Sleep Disorders
When we’re finding it hard to fall asleep, or stay asleep, it can be tempting to think that a drink will solve the issue. In truth, alcohol is often counterproductive to our overall sleep health and sleep hygiene.
Insomnia
Adults who drink to excess often suffer from sleep issues such as insomnia. Unfortunately, sleeplessness and alcohol can exacerbate each other and create a vicious cycle, and there is a link between alcohol abuse and chronic sleep disorders.
Sleep apnea
Sleep apnea is a sleep disorder characterised by abnormal breathing, choking noises, and loud snoring. Obstructive sleep apnea (OSA) is caused by a complete or partial obstruction of the upper airway by the throat muscles. Central sleep apnea (CSA) is less common and occurs when the brain cannot properly signal the muscles that control breathing. As alcohol relaxes the throat and mouth muscles, it can exacerbate such breathing issues.
When to see a GP? If you can’t get to sleep without alcohol, or if you suspect you have sleep apnea, seek urgent medical advice. Sleeping medication should never be mixed with alcohol, as it can be dangerous.
Why can’t I sleep after drinking?
You might wonder, does alcohol help you to sleep? But when we are under the influence, sleep is more likely to be shallow, fitful, and fragmented. Even a glass of wine can have a rebound effect, which is caused by the release of excitatory glutamate after the alcohol has been metabolised by the liver, which can cause us to wake easily in the night.
How to sleep better after drinking alcohol?
Had a bit more to drink than you intended? If you’re prone to insomnia after drinking alcohol, try these hacks to help mitigate some of the worst effects.
- Have a high fibre snack to help regulate the body’s absorption of the alcohol - here are some dream recipes to help you get some decent shut-eye
- Make sure your bedroom is a comfortable, cooler temperature
- Empty your bladder before bed
- Have a small glass of water before bed and keep one nearby in case you wake up with a thirst
- Take milk thistle - a supplement that can support liver function
What are the best drinks before bed? You can find a list of the best bedtime drinks here.