A New Challenge to Widely Held Views on the Role of Sleep

Philosophers, moralists, and scientists have been inter-ested in sleep since ancient times. Although hypotheses and beliefs about the role of sleep have varied over the centuries, many have considered sleep to be an idle state or a sole function of the brain (1). However, suggestions of a link between sleep and metabolic functions can be found in early Roman medicine. Aulus Cornelius Celsus (circa 25 BCE to 50 ACE) argued in favor of “restricted sleep ” for the treatment of extra weight, and Galen (129 to circa 216 ACE) listed “somnux et vigilia ” (sleeping and waking) as important causes of illness (2). With the turn of the 20th century, research about the effects of sleep on health risks has sharply increased. This scientific work is stimulating a public health debate that points to the declining trends in quality and quantity of sleep in modern society as contributing factors to il