A study published in the journal ‘Plos’ has put a finger on the relation between light and its influence on our body rhythms. People with 24-hour access to electric daylight, can disrupt sleep and negatively impact health, well-being and productivity. Professors from the University of Manchester, UK, and the University of Colorado, US, brought together an international body of leading scientific experts to agree on the first evidence-based, consensus recommendations for healthy daytime, evening, and nighttime light exposure.
Recommendations by the study provide guidance to the lighting and electronics industries to aid the design of healthier environments and to improve how we light our workplaces, public buildings, and homes. The study tackles how to properly measure the extent to which different types of lighting might influence one’s body rhythms and daily patterns of sleep and wakefulness. Light affects these patterns via a specialised type of cell in the eye that uses a light-sensitive protein, melanopsin, that is distinct from the proteins in the rods and cones that support the vision.
Since melanopsin is most sensitive to light in a specific part of the visual spectrum, the new recommendations used a newly-developed light measurement standard tailored to this unique property, melanotic equivalent daylight illuminance. An important step, according to the research, will be the integration of the recommendations into formal lighting guidelines, which currently focus on visual requirements rather than effects on health and well-being.
Increasing sophistication in LED lighting technology and the availability of low-cost light sensors are expected to increase the ease with which individuals can optimise their personal light exposure to best support their own body rhythms in line with the new recommendations.
Professor Timothy Brown from the University of Manchester, UK, said, “These recommendations provide the first scientific consensus, quantitative, guidance for appropriate daily patterns of light exposure to support healthy body rhythms, night-time sleep and daytime alertness. This now provides a clear framework to inform how we light any interior space ranging from workplaces, educational establishments and healthcare facilities to our own homes.”
