The effect of light on the body should be recognised in updated lighting standards and guidelines, said experts at LuxLive this week.
Christian Cajochen of the University of Basel explained ways to measure and quantify how lighting influences our bodies. Cajochen’s research focuses on the ‘non-visual’ effects of light – such as the impact that light has on the body clock, alertness and sleep.
Cajochen said Thomas Edison was wrong when he claimed that light does not affect our health and sleep. In fact, light impacts our circadian rhythms more powerfully than any drug.
In the lab, circadian rhythms can be quantified by looking at the secretion of the hormone melatonin, he explained, before describing how lighting has been proven to affect our alertness and our sleep quality. We sleep less deeply following excessive light exposure, especially in the evening.
Research has found that blue-enriched light from TV sets, computers and tablets in the evening and early in the night can elicit an alerting response and delay the circadian response, he said. This can decrease sleep quality and delay the time taken to fall asleep. He pointed, too, to the fact that the risk of insomnia is greater in older people, so there are ‘trade-offs’ between visual and non-visual effects of light.
“We are now trying to implement this into lighting designs, codes and standards,” Cajochen added.
We’ve got used to a very static lighting scheme at work and we don’t like it. We’ve all become zombies"
So how can we bring human-centric lighting into the real world?
Helen Loomes of lighting manufacturer Trilux suggested that organisations and individuals can take small steps to harness more human-centric lighting, such as modifying shift patterns. “A lot is down to how we use the information we have,” she said. “We’ve got used to a very static lighting scheme at work and we don’t like it. We’ve all become zombies. You can use products in different ways, even though we cannot mimic daylight.”
Loomes also suggested that, “we always forget our emotional response to lighting”.
“It really affects how we feel,” she said – pointing to the power of lighting to make an environment feel ‘invigorating’ or ‘depressing’.
And, mocking many manufacturers’ claims to produce human-centric lighting, lighting designer John Bullock said that we live an ‘unnatural’ life in the post-industrial north and west, spending so much of our lives indoors under artificial light. “Cynically, the buyers are looking for maximum productivity,” he added.
Others were more positive. Reine Karlsson of Lund University, for instance, stated that we now have the possibility to vary intensity and colour composition in a way which was not possible with traditional lights. “We have more knowledge of what to do and what not to do,” he said.
Keep updated about the latest advice on lighting and health by visiting http://lightingforpeople.eu/lighting-applications/
Don’t miss Lux’s conference dedicated to Lighting for Health and Wellbeing, on Thursday 22 September 2016 in London.