chapter  5
20 Pages

◾ LIGHT SOURCES AND HEALTH

But one of the main objectives of circadian rhythm manipulation is to help groups of people that could face serious consequences if this rhythm is disrupted. An example of how a disruption of the circadian rhythm can have dire e¥ects on health is the claim, supported by research, that illumination during sleep periods has dire e¥ects on human health such as increased cancer cases. Breast cancer is the oncological condition whose relationship to circadian rhythm §uctuations has perhaps been most extensively studied [1-3].