Sleep and Light (08-03-21)

How does light experienced during the day influence sleep?  Figueiro and colleagues set out to answer this question. They used an online survey “to quantify potential changes in daytime light exposures resulting from teleworking or self-isolating at home [during the Covid-19 pandemic] and how those changes might have affected self-reported sleep quality, psychological health and emotional health. The first survey was administered in early May 2020, and the second survey was administered in September 2020. In broad terms, our analysis indicates that the greater the amount of light one is exposed to during the day (either in the home or outdoors), the better the self-reported sleep outcomes. . . .  The results suggest that spending one to two hours outdoors or staying in a bright to very bright room indoors may improve night-time sleep. These results have important implications for daytime lighting in homes, offices and schools.”

M. Figueiro, C. Jarboe, and L. Sahin.  2021.  “The Sleep Maths:  A Strong Correlation Between More Daytime Light and Better Night-Time Sleep.”  Lighting Research and Technology, vol. 53, no. 5, pp. 423-435,