After “falling back” nearly a month ago, most of us probably believe our bodies have fully adjusted to the reduced amount of sunlight that comes with the end of Daylight Savings Time [DST]. Not so, says researchers from Vanderbilt University Medical Center, who claim that setting the clocks back an hour has a harmful long-term impact on many peoples’ brains.
Sleep specialists at the university analyzed a group of large studies on DST, publishing an article in a recent issue of JAMA Neurology in which they advocated for ending the practice completely. They suggested that by reducing the amount of bright morning light critical for synchronizing the body’s biological clock, DST can cause it to be chronically out of alignment. In addition, they said the “transition seasons” immediately after the one-hour change that occurs every spring and fall lead to sleep deprivation in many, as well as increased risks for heart attack, stroke, accidents caused by daytime sleepiness and other serious issues.
“People think the one-hour transition is no big deal, that they can get over this in a day, but what they don’t realize is their biological clock is out of sync,” said Dr. Beth Ann Malow, a professor of neurology and pediatrics in the center’s Sleep Disorders Division.
“It’s not one hour twice a year. It’s a misalignment of our biologic clocks for eight months of the year … It impacts brain functions such as sleep-wake patterns and daytime alertness,” she added.
Vanderbilt’s home state of Tennessee is one of many states that have either proposed or passed legislation to end seasonal time changes, by either eliminating Daylight Savings Time or making it permanent. However, officially enacting the change would require federal approval. Earlier this year, the Sunshine Protection Act of 2019 was introduced in the U.S. Senate, and is currently undergoing review.