It was interesting to read that a new study has suggested that we don’t sleep any less now than our ancestors did.
In fact, getting an average of six hours’ sleep should be about right says the study – and that we might be obsessing unnecessarily about how much sleep we get.
The study monitored three groups of people (members of the Hadza in Tanzania, the San in Namibia and the Tsimane in Bolivia) who live life much as our forbearers did. And while they stay up for hours after sunset, their only source of light after dark is campfire (therefore melatonin wasn’t suppressed!) and they went to sleep as the temperature was falling and woke when it reached its minimum, at around sunrise.
The study, however, doesn’t take into account quality of sleep. Our ancestors may have only had six hours sleep but maybe it was better quality? Also, let’s not forget they also worked hard outside, didn’t live off a diet of junk food and were certainly not connected to any kind of technology!
Sleep has restorative functions. As we sleep, tissue grows and repairs itself and the immune system is strengthened. The brain also repairs itself during sleep and researchers believe sleep is critical to healthy brain function. In fact, researchers also believe the brain performs actions vital to learning and memory during sleep. Sleep also affects the levels of hormones and other important chemicals circulating in your body. Getting too little sleep disrupts all of that.
Yet research has found that those who frequently get fewer than six hours a night are at significantly increased risk of stroke and heart disease, with evidence that not sleeping enough may ramp up the ‘fight or flight’ response to stress, releasing hormones that speeds up heart rate and raise blood pressure.
So how much sleep do we need? Well it’s six of one and half a dozen of another!
Yes we may not be sleeping any less than our descendants did but our lives today are more notoriously hectic. We’re over worked, over stressed and over wired and we don’t make the time to wind down properly like our ancestors did. Nor do we have the same diet, get the same amount of exercise or the lack of distractions – TV, lighting, mobile phones etc.
What we ultimately need to remember is there is no magic number for sleep and what suits one person, does not necessarily suit another – how you feel the next day indicates how well you slept. If you feel good when you wake up, the chances are you’re getting the right amount of sleep you need.
It’s quality that counts, not just quantity!