Light for health
As part of a wider programme aimed at understanding the relationship between light, sleep and cognition, Professors Derk-Jan Dijk (Surrey Sleep Research Centre) and Anne Skeldon (Department of Mathematics) have worked with director and animator, Peter Caires to create a short film celebrating the collaboration between biologists and mathematicians and explaining the relationship between light, circadian rhythms and sleep timing.
The release of this new animation coincides with the publication of new guidance on healthy daytime, evening and night time indoor light exposure. These expert consensus-based recommendations come from the Second International Workshop on Circadian and Neurophysiological Photometry. The workshop was led and organised by Professors Tim Brown from the University of Manchester and Kenneth Wright from the University of Colorado, and included Surrey co-authors Professors Steven Lockley (Surrey Sleep Research Centre) and Debra Skene (Chronobiology).
The report gives specific recommendations for levels of lighting to promote physiology, sleep and wakefulness in healthy adults. Appropriate light exposure is important for all age groups. Since most of us spend 90 per cent of our time indoors, we need healthy lighting in our homes, schools, workplaces, hospitals and care homes. It's only now that scientists have been able to provide quantitative recommendations both for healthy intensity and spectral composition (wavelength) of light.
We know that we need light to be able to see, but the importance of robust patterns of light and dark for our health is underappreciated. We need bright light during the day, to turn the lights down in the evening and off at night.Professor Anne Skeldon, Professor of Mathematics
The spectral composition of light is also important. Daylight is best if available but if not, indoor lighting should be blue-enhanced during the day. After dusk, for as long as possible before sleep, light exposure should be as dim and blue-depleted (orange-red looking) in the evening, and electronic devices used as little as possible.