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Light sleeper?

This week is all about the relationship between sleep and light…

This wonderful overview explains how light in the evening in the average home is enough to stop most of us getting a good nights’ sleep. – Evening home lighting adversely impacts the circadian system and sleep 

Dr. Robert Karlicek of LESA at RPI explains what that means – and the implications for the lighting sector. – Forces of Change | Intelligent Lighting Systems by IES GO: Lighting Podcasts

This sobering study shows the light level in your room is the highest predictor of breast cancer. This meta-analysis suggests that the dose-response curve rises up to 40lux at the eye and then flattens off. – Light at night and risk of breast cancer: a systematic review and dose–response meta-analysis

‘This laboratory study shows that, in healthy adults, one night of moderate (100 lx) light exposure during sleep increases nighttime heart rate, decreases heart rate variability (higher sympathovagal balance), and increases next-morning insulin resistance when compared to sleep in a dimly lit (<3 lx) environment. Moreover, a positive relationship between higher sympathovagal balance and insulin levels suggests that sympathetic activation may play a role in the observed light-induced changes in insulin sensitivity.’ – Light exposure during sleep impairs cardiometabolic function


Using your mobile phone in the evening gets in the way of a good nights’ sleep – even if you struggle to sleep already. Participants who read a book or a newspaper after 6pm fell asleep 30 minutes earlier – and slept better too… – Effect of Light Emitted by Smartphones at Bedtime on Circadian Rhythm and Sleep: Is It Different between Day Worker and Shift Worker?

This brief article suggests that the cool blue lighting that some airlines use to create a fresh feeling in the cabin may be great for the crew – Better than a coffee – but not so good for getting you in the holiday mood… – Blue Alert: Research Illuminates Effects of Aircraft Cabin Mood Lighting

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