Melatonin is a powerful hormone and antioxidant with numerous effects on the metabolism and the health of humans. This volume provides a wide variety of expert reviews on the biology of melatonin relevant to health. Beginning with a history of melatonin and its relation to circadian rhythms, the book examines its use in a host of applications, including gastrointestinal diseases, anesthesia and surgery, bone health, breast cancer, cardiovascular diseases, diabetes, and age-related macular degeneration and uveitis. It also examines applications related to melanoma, solar skin damage, collagen synthesis, the prevention of DNA damage, mental disorders, sleep, and issues related to jet lag and shift work.