Tackling depression and obesity could be key to addressing drowsiness during the day, according to a new trio of US studies.
Obesity and depression have been identified as the biggest risk factors for excessive daytime sleepiness (EDS) by researchers at Penn State University.
However, while linked to high blood pressure, heart disease and stroke, there is also concern about the increased risk of accidents among EDS sufferers, which could be a particular problem among the elderly.
Principle investigator in all three studies, Alexandros Vgontzaz, explained: "The 'epidemic' of sleepiness parallels an 'epidemic' of obesity and psychosocial stress.
"Weight loss, depression and sleep disorders should be our priorities."
Another study published earlier this week suggested that sleep disturbance in adults could also be the result of adults being afraid of the dark.
Nearly half of students taking part in a Ryerson University sleep study admitted to being afraid of the dark.
Read about support and personalised care at Barchester care homes for anyone with mental health concerns.