How are you sleeping at the moment? The odds are, not very well. A National Sleep Survey earlier this year found that three-quarters of the people questioned were sleeping badly, with women appearing to be the worst affected.
And this all matters because a good night’s sleep is really important, not just for our mental wellbeing but also for our physical health and, in particular, our immune system. It’s while you’re asleep that your body produces antibodies and killer T cells, which fight off infections.
Inevitably, increased stress is playing its part in the current national sleep problem — but so is alcohol.
A National Sleep Survey earlier this year found that three-quarters of the people questioned were sleeping badly, with women appearing to be the worst affected. Dr Michael Mosley is seen in his pyjamas at home
According to the latest figures from Public Health England, the number of people drinking at levels considered higher risk has risen from one in nine before lockdown, to one in six.
Now, lots of people have a late-night tipple because they believe that alcohol helps them sleep better. But recent research shows quite clearly that this is a myth.
Although having a drink with friends can boost your mood, alcohol is a cognitive depressant, meaning it slows down your brain activity.
That is why drinking makes you sleepy, particularly when you drink late at night when your body clock is triggering other changes to ready you for sleep.
Depending on your age and sex, it takes your body two to three hours to break down a pint of beer or a large glass of wine — during that time the alcohol will disrupt your deep sleep, which is when a lot of vital repair goes on.
One theory is that alcohol reduces the ‘rest and digest’ side of the nervous system, allowing the ‘fight or flight’ side to dominate, so you’re kept in a state of higher alertness.
Although having a drink with friends can boost your mood, alcohol is a cognitive depressant, meaning it slows down your brain activity
So, after drinking you may fall asleep rapidly, but you’re also likely to have more fragmented sleep, with regular short wakings that you may not even notice. This also explains why, after a drink, people often report more disturbing and disruptive dreams.
Although we dream throughout the night, we don’t normally remember most of those dreams — we only really remember those happening just as we wake up.
But because alcohol means you wake up more often during the night, you’re more likely to remember dreams. And if the reason you drank alcohol in the first place was because you were stressed, those dreams are also likely to be more vivid and stress-filled.
How much difference does late-night drinking really make? This was the subject of a U.S. study, published last year in the journal Sleep, where scientists looked at how three different substances, caffeine, alcohol and nicotine, affected sleep.
The participants — 785 healthy men and women — wore wrist actigraphs, monitors that measure how much sleep you’re getting, for a week. They also recorded if and when they had caffeine, alcohol or a cigarette within four hours of going to bed.
The researchers found that smoking had the worst impact, cutting sleep by an average of 45 minutes (probably because nicotine is a stimulant). The effects of alcohol were more subtle.
On the nights they drank, the volunteers didn’t sleep any less, but their sleep was less refreshing and more disrupted, which would then affect their long-term health and immunity.
Perhaps surprisingly, caffeine didn’t make a difference to how long or how well they slept.
If you’re a regular drinker and suffer from insomnia, then it may well be worth giving up for a while. A couple of weeks ago I decided to give up alcohol for a month, as part of Sober October. I’m wearing a sleep monitor every night and it’s shown that the quality of my sleep has indeed improved.