Blue light regulates Ôbody clockÕ

The human eye is sensitive to short wavelength-visible light and transmits information to the Ôbody clockÕ which may make it possible to manipulate waking and sleeping rhythms.
The discovery comes from research from the University of Surrey. The possibility emerges that this type of light Ð which is dark blue in colour Ð could be used to adjust the body clocks of shift workers, those affected by seasonal affective disorder (SAD) or travellers on long-haul flights to avoid jet leg.
Exposure to blue light seems to suppress melatonin levels which cannot be explained by activity of known photoreceptors. ÔOur findings have exciting future applications,Õ said Dr Debra Skene, who led the university research team. ÔThe applications we imagine will be effective in the field of lighting for health.
ÔSome sections of the population have a particular need to adjust and manipulate their circulation axis, or body clocks, in order to be able to function more effectively during hours of the night when our bodyÕs response is to tell us to sleep.Õ
The article has been published in the Journal of Physiology and is available on the internet at www.jphysiol.org/cgi/con tent/abstract/535/1/261