The best thing you can do for your health:
Do you think you got enough sleep this past week? Can you remember the last time you woke up without an alarm clock, feeling refreshed, not needing caffeine?
Surveys by the UK Sleep Council and YouGov reveal that one out of every three people on the streets of Britain regularly suffer from poor sleep. I doubt you are surprised by these facts, but you may be surprised by the consequences.
Remarkable sewage system
Insufficient sleep is now one of the most significant lifestyle factors influencing whether or not you will develop Alzheimer’s disease. During sleep, a remarkable sewage system in the brain, called the glymphatic system, kicks into high gear. As you enter deep sleep, this sanitisation system cleanses the brain of a sticky, toxic protein linked to Alzheimer’s, ■ little sleep swells concentrations of a hormone that makes you feel hungry while suppressing a companion hormone that otherwise signals food satisfaction. Despite being full, you will still want to eat more. It’s a recipe linked to weight gain in sleep-deficient adults and children alike. Worse, should you try to diet but don’t get enough sleep, it is futile, since up to 70 per cent of the weight you lose will come from lean body mass, not fat.
Legal ‘drug’
Related is the association between plentiful slumber and athletic performance. Sleep is perhaps the greatest legal performance-enhancing “drug” that few people are taking advantage of. Obtain less than eight hours of sleep a night, and especially less than six hours a night, and the following happens: time to physical exhaustion drops by 10 to 30 per cent, as does aerobic output; limb extension force and vertical jump height are reduced; peak and sustained muscle strength decrease.
And then there is injury risk. Relative to sleeping nine hours a night, sleeping five to six hours a night will increase your chances of injury across a season by more than 200 per cent. Routinely sleeping less than six hours a night also compromises your immune system, significantly increasing your risk of cancer. So much so, that recently the World Health Organisation classified any form of night-time shift work as a probable carcinogen.
Blood sugar affected
sugar levels so profoundly that you would be classified as pre-diabetic. Short sleeping increases the likelihood of your coronary arteries becoming blocked and brittle, setting you on a path towards cardiovascular disease, stroke and congestive heart failure.
Strikingly, all it takes is one hour of lost sleep, as demonstrated by a global experiment performed on 1.6 billion people across more than 60 countries twice a year, otherwise known as daylight saving times. Sleep disruption has further been associated with all major psychiatric conditions, including depression, anxiety and suicidality. Indeed, in my research over the past 20 years, we have not been able to find a single major psychiatric condition in which sleep is normal.
Recent findings demonstrate that individuals who routinely sleep five hours a night have a 65 per cent increased risk of dying at any moment in time, relative to those getting seven to nine hours a night.
Impaired performance
Scientists such as myself have even started lobbying doctors to start “prescribing” a good night’s sleep (though certainly not sleeping pills). As medical advice goes, it’s perhaps the most painless and enjoyable to follow. The irony here is that, in medical practice, inadequate sleep leads to inadequate health care. Junior doctors working a 30-hour-plus shift will make 460 per cent more diagnostic mistakes than when well rested.
Seasoned physicians can suffer the same compromise of medical skills.
A senior attending surgeon who has slept only six hours or less the previous night is 170 per cent more likely to inflict a serious surgical error on a patient, relative to when they have slept adequately. It is worth noting evidence from scientific studies showing that after 22 hours without sleep, human performance is impaired to the same level as that of someone who is legally drunk.