Sleep & circadian rhythms

Many aspects of human physiology and behaviour are dominated by our 24-hour – or circadian– rhythms. For example, sleep/wake cycles, alertness and performance patterns are governed largely by exposure to daylight.

Over the last 150 years, artificial light and staggered working schedules have seemingly ‘liberated’ us from the natural cycles of light and dark, but this separation from nature comes at a cost. Many children in schools and adults in theworkplace are isolated from natural light during the day, while being exposed to too much artificial light in the evenings and at night. High levels of morning light increase alertness, allowing better performance and cognitive function during the day, while sufficient exposure to daylight throughout the day encourages better sleep at night.

Around 85% of the working population needs an alarm clock to get up during the week, and only 7% of us get sufficient sleep on workdays. Poor sleep at night has been linked to lower job performance, higher risk of work accidents, difficulties in making decisions at work, and higher levels of absenteeism.

Insufficient sleep and reduced sleep quality can have serious consequences for children’s development and school performance, and this is exacerbated in the teenage years when the body has a tendency to remain alert later into the evening.

In our sleeping environments, we need to consider the amount of light, noise levels, temperature, and air quality, since they all have a significant impact on sleep. Research shows that poor sleep quality or sleep disruption are linked to reduced cognitive function, stress, depression, poor social interaction, metabolic and cardio-vascular disease, increased susceptibility to infection - and even cancer. 


of the population needs an alarm clock to get out of bed in the morning


of the population gets sufficient sleep on workdays

Related content

Contact usontact us: