Significance: “Exposure to brighter nights and darker days causes circadian disruption, which accompanies poor health outcomes that increase mortality risk. Whether personal day and night light exposure predicts mortality risk is not known. This study captured ~13 million hours of data from light sensors worn by ~89,000 individuals who were over 40 y of age. Those with brighter nights and darker days had higher risk of premature mortality, after accounting for sociodemographic and lifestyle factors. Avoiding night light and seeking day light may promote optimal health and longevity, and this recommendation is both accessible and cost-effective.”

Windred DP, Burns AC, Lane JM, Olivier P, Rutter MK, Saxena R, Phillips AJK, Cain SW. Brighter nights and darker days predict higher mortality risk: A prospective analysis of personal light exposure in >88,000 individuals. Proc Natl Acad Sci U S A. 2024 Oct 22;121(43):e2405924121. doi: 10.1073/pnas.2405924121. Epub 2024 Oct 15. PMID: 39405349.

https://www.pnas.org/doi/10.1073/pnas.2405924121