Sleep your way to a longer, healthier life
By TV doctors Chris and Xand van Tulleken
Good quality sleep, night after night, is critical to virtually every aspect of your mental and physical health. That’s why getting enough of it is key to feeling and looking younger, and living well for longer.
The evidence from the science for how lack of sleep can put strain on our bodies and age us is alarming. one night of poor sleep can undermine your immune system, while chronic poor sleep increases your risk of type 2 diabetes and diseases including dementia and cancer.
More recently it’s been shown to shorten telomeres, the protective ‘caps’ on the end of our strands of dnA which indicate biological age. every time our cells divide, a bit of our telomeres vanishes. And when they’re gone, they’re gone. so the last thing we want to do is hasten our telomeres’ shortening by sleeping badly.
shortening of telomeres has been linked to heart disease, chronic stress, depression and obesity, all of which have a dreadful impact on your quality of life.
sleep clearly matters for both our short-term and long-term health, which is why we consider sleeping better to be one of our four pillars of anti-ageing, and why today we’re going to show you how to improve your sleep.
We are terrified by the thought of not getting enough sleep. As junior doctors we worked epic hours — Chris hallucinated with fatigue and fell asleep while talking to patients. he knows he is a terrible doctor between 3am and 4am.
Xand spent a couple of years commuting between north America, where he had a job and a son, and the UK, where he was presenting television, amassing more than 50 transatlantic flights a year. he gained 4 stone and would fall asleep over dinner, in meetings and during filming.
BUT what can you do to improve your sleep, or at least improve how well you function when you’re not optimally rested? As part of our new BBC2 series, The Twinstitute, we tried to find out. Using ourselves as guinea pigs, we called on 30 sets of identical twins, taking advantage of their matching dnA, to try memory tests, physical challenges and diet- based experiments to investigate a range of popular theories about health and wellbeing.
We’ve used these experiments and other research to put together the anti-ageing series that’s running in the Mail this week. on saturday we focused on the brain and how to improve and protct your cognitive function. Today, we unpick the mysteries of sleep, showing how you can get maximum rest out of the time you spend in bed — so you can live well for longer.
ARE YOU GETTING SEVEN HOURS?
The sleep Council estimates that one third of Britons get only five to six hours of sleep a night, and 12 per cent of Britons sleep for less than five hours a night.
This falls short of official recommendations — U.s. charity the national sleep Foundation believes adults should aim for seven to nine hours (seven to eight for the over-65s).
We ourselves average five to seven hours — not nearly enough to function well and avoid premature ageing. We typically fall asleep late and there’s never the opportunity for a lie-in, so exhaustion accumulates.
paradoxically, Chris has found that having a young child has imposed a good sleep routine. For many it can affect sleep horribly — no wonder people say having a child ages you.
Life is impossible if you have a lot of 5am starts and you’re going to bed at midnight, so Chris and his wife have worked on a decent evening routine.
The screens aren’t always off by 9pm, but life is more bearable with lights out by 11 — even if their 18-month- old daughter does get them up in the night.
We all know how grim it can be to function after a bad night — but the harm of even one night’s poor sleep was graphically illustrated by one of our experiments for The Twinstitute.
We separated two sets of identical twins into two camps and made our twin guinea pigs stay awake for 30 hours.
As they forced themselves to stay awake, our twin testers noticed a shocking drop in their reaction times and judgement — as if their brains had ‘aged’.
To see if there are any tricks to protect you from a bad night’s sleep, before the experiment one team of twins ‘banked’ an extra four hours of sleep by going to bed an hour early for four nights; the other team were allowed 12 20- minute naps during the experiment to see if the snoozes could refresh them.
We thought the power nappers would be at an advantage, as power napping has been shown to be effective in lots of studies.
To test their risk assessment, we asked our two pairs of twins to blow up balloons to the point just before they would burst. Then reaction times were measured by how quickly they responded to a light flashing on a board.
After 30 hours of sleep deprivation, the nappers were the worst affected — the balloon
bursting rate rose to 24 per cent but the sleep bankers burst only 10 per cent of their balloons.
The reaction times of the sleep bankers didn’t really change but the nappers’ reaction times dropped significantly.
As a final test, we asked both sets of twins to try to land a 747 jumbo jet in a simulated cockpit. It requires risk management, co-ordination, memory and nerve, which are all compromised by a lack of sleep, and which tend to deteriorate as we age.
Everyone struggled with confusion and disorientation, but two planes were successfully landed — both by the twins who had done the sleep banking.
Scans back these findings up, with studies showing that sleeplessness appears to inhibit the frontal lobe of the brain, which causes the sleep deprived to make poor decisions.
This ties in with research showing that sleep is when your brain clears out toxins (including the ‘plaques’ which can be a hallmark of Alzheimer’s), negative thoughts and any trivial details you no longer need — clearing out the garbage and allowing the brain to rejuvenate.
DON’T DRIVE AFTER TOO LITTLE SHUT-EYE
Poor performance due to lack of sleep has been shown to be like being drunk.
A 2017 study from Tel Aviv University in Israel showed that brain cells — or neurons — deprived of sleep respond slower and send weaker signals than rested neurons. This might be why fatigue feels like being under the influence of alcohol — with the same memory and concentration lapses.
And it is why driving (or landing a 747) is so dangerous when tired. It actually takes longer for the exhausted brain to see things — messages from eyes to brain to muscles slow down.
Sleep is also when the brain undergoes repairs: short- term memories are converted to long- term memories, thought processes are organised, and new brain connections are built, restoring it.
Large studies have shown that poor sleep, over time, can even lead to brain shrinkage. The theory is that when you are sleep- deprived, the brain’s waste clearance cells prune the very cells they should be trying to preserve, ageing the brain rapidly.
TOO TIRED TO RESIST JUNK FOOD CRAVINGS
LACK of sleep certainly leaves you vulnerable to cravings, which can lead to over-eating and weight gain, taking years off your life. During the day, chris says he can resist the snack machine without too much effort. At night, when he’s tired, it’s another story. Pizza and sweets become the staple.
It’s not clear why this happens. It’s prob-ably partly because the effort of resisting temptation becomes too much, but there are hormonal changes accompanying sleep deprivation that seem to drive consumption of high-calorie foods and can even induce a temporary state like type 2 diabetes.
This might explain why people who don’t sleep enough are more likely to develop type 2 diabetes, which is linked to dementia and cognitive decline, reducing your ‘health span’.
The chemicals released during sleep calm inflammation and bolster immunity. Studies have shown that better sleep can lead to fewer colds and immune- related disorders, and even a lower risk of cancer. So getting closer to eight hours of sleep a night can make a dramatic differ-ence to our health, how our brains age and how well we can use them as we get older. Yet how many of us let bedtime slip by an hour to watch just one more episode of that box set, have another drink, or do a little more work, thinking it won’t make a difference? Well, now there’s good evidence that it certainly does.
THE Twinstitute is on BBC2 on Wednesdays at 8.30pm.