On April 10, the U.S. Senate Committee on Commerce, Science, and Transportation held a committee hearing titled, “If I Could Turn Back Time: Should We Lock the Clock?”, which explored the options for ending the biannual time change currently required by daylight saving time. The committee invited several witnesses to testify, including Dr. Karin Johnson, AASM Advocacy Committee member and chair of the Coalition for Permanent Standard Time. Dr. Johnson argued that permanent standard time is the healthy choice, promoting physical health, mental health, performance and safety.
Standard time aligns best with human circadian biology and provides distinct benefits for public health and safety. Standard time is closely aligned with the position of the sun, which is important for the body because sunlight is the most powerful external cue for the human circadian rhythm. This internal “body clock” regulates the timing of alertness, sleepiness, and other biological functions. By artificially shifting the clock time an hour forward, daylight saving time causes a misalignment between clock time and solar time, interfering with our circadian timing. This disruption is associated with an increased risk of obesity, metabolic syndrome, cardiovascular disease, and depression.
Watch the Committee Hearing to see Dr. Johnson’s full testimony.
Position Statements
- AASM: Permanent standard time is the optimal choice for health and safety
- NSF: Permanent standard time
- SRS: It is time to abolish the clock change and adopt permanent standard time in the United States
- SRBR: Why should we abolish daylight saving time?