Colin A. Espie PhD, DSc
Professor of Sleep Medicine, Sir Jules Thorn Sleep and Circadian Neuroscience Institute, University of Oxford
Russell G. Foster
Professor of Circadian Neuroscience, University of Oxford
When we strip things down and explore the foundations of our needs as human beings, what do we find? We discover that sleep is one of the most important ingredients that give us the capability to live our lives.
Sleep plays a central role in so many things. These include the renewal and repair of our body tissues, the workings of our metabolism, our physical growth and development, our ability to fight infection, our learning skills and memory and our ability to regulate our emotions. Sleep touches absolutely everything.
The quality of our daytime alertness, energy, productivity and mood are all heavily dependent upon sleep. Good quality sleep is essential for mental health and wellbeing at every age and stage in life. Research shows that when insomnia is effectively treated people are more likely to see their depression lift.
Sleep patterns are different for everyone
Getting the right amount of sleep is important. Although the average adult requires 7-8 hours, there is variation from person to person. Some people need less, but others need more. These are just normal individual differences and we need to experiment to find the right fit for us. Likewise, when we get our best sleep varies from person to person.
Research shows that when insomnia is effectively treated people are more likely to see their depression lift.
Some people are morning people and others are evening people. You have probably heard about ‘larks’ and ‘owls’. These differences depend upon the genetics of our body clock or ‘circadian rhythms’, our age and when we see light.
Importance of circadian rhythms
Our circadian rhythms help time our sleep and keep the rest of our biology in synchrony with the complex demands imposed by the Earth’s 24-hour rotation and the light/dark cycle. Circadian rhythms allow our bodies to deliver the right materials, in the correct concentration, to the right parts of the body at the correct time of day.
All the processes underpinning life must be synchronised to the rotation of the Earth and to each other. Light regulation of the clock allows this to happen. Without this daily re-setting, circadian and sleep systems fail. Then we simply don’t function well on a day-to-day basis and, as a result, we become more vulnerable to develop mental and physical health disorders.
