Sleep is a major health problem. Sleep deprivation and poor sleep are associated with many health conditions including cancer, diabetes, heart attack and depression. Lack of sleep dramatically affects performance and concentration; being awake for more than 24 hours is comparable to being over the UK drink-drive limit.

Sleep disturbance is the most common expression of mental ill-health. Sleep deserves parity alongside other healthy lifestyle behaviours such as being physically active and eating a balanced diet. Research shows that getting enough sleep is ranked second only to not smoking in terms of what the public believe is most important to optimise their health and wellbeing.

The first two items are based on recommendations that, to synchronise with the circadian rhythm, people should always aim to go to sleep and to wake up at the same time every day. These factors are most readily achievable by those with poor sleep quality.

The third and fourth items relate to the quality of sleep that people perceive they get.