Sleeping too long or too short is associated with a higher risk of various illnesses, such as stroke, depression, type II diabetes and diseases that reduce blood flow from the heart. Not sleeping enough can lead to being overweight and obesity.
Changes in society, such as the 24-hour economy and the increasing use of digital devices (screen use, blue light, continuous stimuli) can mean that good and sufficient sleep is no longer guaranteed. Intensive use of smart phones, tablets and/or PCs in the hour before going to sleep is associated with less sleep and a lower sleep quality in adults. Getting enough exercise is associated with a normal sleep duration and a good sleep quality.