Who do I feel so tired the morning after the night before? 

A nightcap before bedtime may send you off to sleep faster, but very few people realise that it can disrupt your night’s sleep.

“A lot of people don’t make the connection between feeling tired and drinking too much,” says Jessica Alexander from the Sleep Council. “Alcohol is one of the ‘three evils’ when it comes to disrupting sleep – the other two being caffeine and smoking.

“If you find yourself regularly drinking above the daily unit guidelines, your body may be constantly trying to catch up and you may not feel fully alert or equipped to deal with the stresses and strains of daily life” she adds.

The London Sleep Centre team says studies show alcohol disrupts our normal sleep cycles. Despite the fact that alcohol initially sends us off to sleep faster, as the alcohol starts to wear off, our bodies come out of deep sleep and back into REM sleep, which is much easier to wake from. When alcohol is consumed before sleep too often, it has been proven to cause insomnia.

Dr Irshaad Ebrahim, medical director at the London Sleep Centre, said: “We should be very cautious about drinking on a regular basis. Sleep may be deeper to start with, but then becomes disrupted.”

Chris Idzikowski, Director of the Edinburgh Sleep Centre, adds: “With increasing doses, alcohol suppresses our breathing. It can turn non-snorers into snorers and snorers into people with sleep apnoea – where the breathing’s interrupted.”

The results of Dr Ebrahim’s team’s studies indicate that alcohol appears to change sleep in three ways. Firstly, it accelerates the time it takes for us to fall asleep. Secondly, it sends us into a deep sleep. Unfortunately, thirdly, our sleep is then fragmented in the second half of the night.

Overall, if you keep your alcohol levels low close to bedtime, then you will wake up feeling fresher! On average it takes one hour to ‘metabolise’ one unit, but this varies widely from person to person.