Can’t sleep without your nightlight?
This is Sandra Tsing Loh with the Loh Down on Science.
We used to sleep in real darkness. Now? Screens brighten our nights. Could this affect our lifespans?
Enter Daniel Windred and team from Flinders University. They studied nearly NINETY THOUSAND British adults over forty. All participants wore wrist light sensors for a week. Their heart records were monitored for TEN YEARS after.
Participants were split into groups based on brightness during sleep. For the brightest sleepers? The risk of heart attack mounted to FIFTY PERCENT! And this factored in exercise, and diet.
Why the heart trouble? Researchers suspect light may be throwing off our body’s internal clock.
So, give your heart a hand and flip that switch!
Windred, D. P., Burns, A. C., Rutter, M. K., Lane, J. M., Saxena, R., Scheer, F. A. J. L., Cain, S. W., & Phillips, A. J. K. (2025). Light Exposure at Night and Cardiovascular Disease Incidence. JAMA Network Open, 8(10), e2539031. https://doi.org/10.1001/jamanetworkopen.2025.39031