By James Brown, Education and Public Engagement Manager, Biochemical Society
How much sleep did you get last night? Did you manage your full eight hours? Or do you prefer to burn the candle at both ends? Do you ever worry about how much sleep you get? I’m no stranger to a good lie-in but after hearing Matthew Walker, director of the Center for Human Sleep Science at the University of California, Berkeley, even I feel like I’m short changing myself in the sleep stakes. Matthew was talking at the Royal Institution about how he believes we are (lack of) sleep walking into a potential health nightmare caused by too little shut-eye.
In common with nutritional advice, most of us get the majority of our information about the health benefits of sleep from newspapers and the mainstream media. There’s a lot of conflicting information floating around. For every time you get told that you need your full eight hours, there are numerous high powered executives and leaders extolling the virtues of a brief four or five. If you ever see me after four hours sleep, you’ll be lucky if I can remember my name, let alone make important decisions about nations, but there is a macho pride in living the old maxim that ‘there’s plenty of time to sleep when you’re dead’. As it turns out, this is likely to come around much sooner for those who aren’t getting enough kip.
The truth is, that even though we may not understand sleep as well as we might like, there is a wealth of data and information out there about how important it is and Walker is on a mission to give clear, unequivocal advice about it. Walker himself is a confident, quick witted and amiable speaker. He has a great sense of humour, which is most definitely for the best, because his talk is packed full of examples of how we are causing ourselves untold damage with our addiction to wakefulness. For example, Walker told the audience about one study in which participants who had just one week of short sleep (5-6 hours) would be categorised as pre-diabetic. Similarly, in a different study, just one single night of 4 hours sleep resulted in a 70% reduction in natural killer cell activity. These physiological impacts can have huge consequences for cancer patients; a trial in mice showed that disrupted sleep resulted in a 200% increase in cancerous growth. Sleep loss, it turns out, is an accelerant of cancer. In another study, 1 week of six-hour sleep distorted the gene activity of 711 genes, either making them overactive or underactive. Those which were seen to be overactive tended to be linked to tumour promotion, inflammation, stress responses and cardiovascular disease. These effects are so pronounced that the World Health Organisation has classified night shift work as a carcinogen. What struck me the most from some of these examples, was the fact that it was not just extreme sleep deprivation that was having these effects, they were occurring after just marginally shorter or disrupted sleep. Shortened sleep patterns have a huge effect on mental health, cardiovascular health, PTSD, suicide, depression, anxiety, Alzheimers, memory, and learning. Without sleep both before and after learning, the ability of our brains to commit things to memory is severely reduced. The importance of sleep for learning, coupled with the increased needs of teenagers makes a strong case for later starts for schools. Edina County in Minnesota moved the start of the school day from 07:25 to 08:30 and saw some shocking results. Academic achievement went up, behaviour problems, truancy, and psychological issues went down. But most surprisingly of all, the student’s life expectancy went up. The leading cause of death among US teenagers is car accidents. A similar program in Teton County, Wyoming saw that one hour of extra sleep reduced car crashes by 70%. Even relatively short changes in sleep patterns can have significant effects – day lights savings accounts for a 24% increase in heart attacks in the spring and a concurrent 21% decrease in the Autumn. When Greece phased out the afternoon siesta, they saw an increase in fatal heart attacks of 35%. During his talk, Walker picked out these and a plethora of other examples to help him make his point; the effect being akin to being continually shaken awake by an insistent good Samaritan.
These examples make for stark and uncomfortable reading. With his work at the Center for Human Sleep Science, Walker is hoping that he can communicate this data to where it is needed most. With a new book, Why we sleep?, and a series of media appearances, he is shouting as loud as he can about the benefits of sleep. He is certainly gathering good column inches, but will it make a difference to how people approach their sleep? Is it too big a cultural change for us to turn back the tide of longer days? Perhaps with sleep, unlike with diet and exercise it will be less difficult to persuade people to put their health first – after all, who doesn’t like to cosy up in bed? With that in mind, I’m off for an early night; sleep tight.
