UW News

circadian rhythms


November 2, 2022

Permanent daylight saving time would reduce deer-vehicle collisions, study shows

University of Washington researchers found that adopting permanent daylight saving time in the United States would reduce deer-vehicle collisions and likely prevent an estimated 36,550 deer deaths, 33 human deaths, 2,054 human injuries and $1.19 billion in costs each year. Deer-vehicle collisions would decrease under permanent DST because skies would be brighter later into the evening.


January 27, 2021

On nights before a full moon, people go to bed later and sleep less, study shows

picture of the moon

Sleep cycles in people oscillate during the 29.5-day lunar cycle: In the days leading up to a full moon, people go to sleep later in the evening and sleep for shorter periods of time. The team, led by researchers at the University of Washington, observed these variations in both the time of sleep onset and the duration of sleep in urban and rural settings — from Indigenous communities in northern Argentina to college students in Seattle, a city of more than 750,000. They saw the oscillations regardless of an individual’s access to electricity, though the variations are less pronounced in individuals living in urban environments.


December 12, 2018

Teens get more sleep, show improved grades and attendance with later school start time, researchers find

In 2016, Seattle Public Schools pushed back the start times for the district’s 18 high schools by 55 minutes, from 7:50 a.m. to 8:45 a.m. And as hoped, teenagers used the extra time to sleep in.


August 26, 2014

Health Digest: Ebola outbreak, HIV persistence, kids’ sleep routines

Ebola virus

UW Health Sciences News Digest: Ebola outbreak, HIV persistence, back-to-school sleep routines