New Year's Eve warning as doctors reveal how alcohol ruins your sleep

Tonight is Hogmany and people across Scotland will be ringing in the New Year as they wave goodbye to 2024. Scots will gather with loved ones to raise a toast at the bells - and often have a fair few more drinks too.

But revellers must take measures to safeguard their sleep or risk unwanted health repercussions long into the 2025, a doctor has warned. After several weeks of office parties and festive fun, many of us will be familiar with the unpleasant sensation of waking up with a hangover.

But doctors warn that the impacts of alcohol on our sleep patterns can be far more harmful – and difficult to shake off. So how does drinking alcohol affect our brains and bodies, and why does this sabotage our sleep?

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What happens to your body when you drink alcohol?

“When you drink alcohol, your body prioritises breaking down alcohol over other bodily processes, leading to the accumulation of toxic byproducts like acetaldehyde, which can cause inflammation and fatigue,” explains Dr Ashwin Sharma, a leading medical professional at MedExpress.

This tiredness is only worsened as your body responds to the intoxicating effects of alcohol. Although booze initially depresses the central nervous system to produce feelings of relaxation, your brain counteracts these effects by becoming more active. This leads to restlessness, disrupted sleep, and increased heart rate during the second half of the night.

Drinking too much alcohol can also affect the part of the brain that regulates your internal clock, potentially inferring with your sleep patterns.

How does a night of drinking impact the quality of your sleep?

Experts warn that the quality of your sleep is almost always worse after consuming alcohol.

Dr Steve Allder, consultant neurologist at Re:Cognition Health, explained: “Alcohol suppresses rapid eye movement (REM) sleep during the first half of the night. As the body metabolises the alcohol, there’s a rebound effect, leading to lighter, more fragmented sleep in the second half.

The scientist added that alcohol disrupts the restorative properties of slow-wave sleep, leaving you feeling less refreshed the next day. It is also a diuretic, which causes frequent urination and dehydration – all of which encourages fragmented sleep and early morning awakenings.

What are the short-term consequences of disrupted sleep after drinking?

A night of low-quality sleep thanks for alcohol consumption is likely to leave groggy Scots with slower cognition and mood changes. Dr Sharma warns that people who have been drinking will wake up feeling tired, sluggish, and mentally foggy due to disrupted sleep and dehydration.

He added: “Alcohol can also cause headaches, dizziness, and a dry mouth due to fluid loss. Mood disturbances like irritability, anxiety, and even depression are also common, driven by neurotransmitter imbalances caused by alcohol’s effects on the brain.”

What are the effects of sustained drinking over the holidays?

After several days of drinking alcohol over Christmas, continuing to knock back the booze on New Year’s Eve can take a serious toll on your sleep pattern. Drinking over a sustained period creates a cycle of poor sleep and increased fatigue, which means that you risk starting the new year not just with a hangover, but with a chronic sleep debt too.

This sleep deprivation makes it harder to function during the day, derailing the best intentions for embarking on new hobbies and health regimes in January.

“Repeated alcohol consumption can also weaken your immune system, making you more susceptible to infections,” Sharma adds. Even more alarmingly, alcohol-related sleep disruptions can lead to serious mental and physical problems like chronic fatigue and increased risk of depression or anxiety.

Over time, this sleep deprivation can also contribute to cardiovascular problems and reduced cognitive function, increasing the risk of various chronic diseases.

How can you enjoy a drink while protecting your sleep this New Year’s Eve?

“To mitigate alcohol’s effects on sleep, try pacing yourself by drinking water between alcoholic drinks to stay hydrated,” advises Dr Sharma. He adds that health-conscious Scots should also avoid drinking alcohol within three hours of going to be, to give the body time to metabolise the fluid.

Engaging in light-exposure therapy during the daylight hours can likewise help to regulate the circadian rhythm after disrupted sleep, the doctor advises. You can do this by sitting in front of a light box, or by getting out into the fresh air for a morning.

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