Sleep, nighttime
As well as sleep itself being important, other aspects of the familiar 24-hour cycle can be important in many ways.
Leukaemia - Exposure to light at night may be implicated in the 50 per cent increase in leukaemia in children under five since the 1950s. Professor Russel Reiter, of the University of Texas said in London in early September 2004 that exposure to light at night disrupts the body's circadian rhythms and suppresses nocturnal production of the hormone melatonin. "As an antioxidant, in many studies melatonin has been shown to protect DNA from oxidative damage. Once damaged, DNA may mutate and carcinogenesis may occur" he said. (Canberra Times, 13 September 2004)
Are you getting enough sleep? - If you are not being kept awake by television, the internet or some other screen, coffee or non-paleolithic cause and you are not using an alrm or other external means of waking up in the morning, you are probably getting the right amount of sleep.
Evfit home On to evolution and health On to sunlight Comment on this page
Page last up-dated 5 December 2007