Researchers say seasonal clock changes could disrupt sleep cycles and intensify existing mental health conditions for some people

Carlos Carrillo López, New Mexico State University

LAS CRUCES - Daylight saving time isn’t just a seasonal inconvenience – it may also pose significant neuropsychological risks for the hundreds of millions of people worldwide who experience biannual clock shifts, especially those living with chronic mental illnesses.

That’s according to a major new study by a team of researchers from New Mexico State University’s College of Health, Education and Social Transformation and the University of Nevada, Las Vegas’s Kirk Kerkorian School of Medicine.

Drawing on more than 60 studies worldwide spanning chronobiology, psychiatry, neuroscience and public health, the researchers have concluded that the one-hour time shift caused by daylight saving time acts as a population-wide circadian stressor – and that people with depression, bipolar disorder, anxiety disorders, PTSD, ADHD and psychotic disorders face amplified risks during the days and weeks following a clock change. The study was published in the journal Brain Sciences.

“We now have evidence that daylight saving time changes disrupt circadian rhythms in ways that are harmful to people with mental health and sleep-related difficulties,” said Elizabeth England-Kennedy, an assistant professor of public health at NMSU who was part of the research team. “Healthcare providers may want to prepare their clients in advance for these negative effects.”

The research team also included Jagdish Khubchandani of NMSU and Kavita Batra of UNLV, who were the lead authors on the study, as well as Karen Kopera-Frye of NMSU. Their findings come amid a growing push to end seasonal clock changes in the United States.

“We change the clocks in a single night, but the brain does not adjust that quickly. Daylight saving time silently disrupts the body’s biological clock, influencing sleep, emotional regulation, cognition, and psychiatric stability,” Batra said. “For millions living with chronic mental illness, this is more than lost sleep; it may represent a preventable public health risk or serious exacerbation of existing symptoms.”

The study urges clinicians to treat daylight saving time transitions as predictable and modifiable risk windows. It recommends offering patients’ anticipatory guidance on gradually shifting sleep schedules several days before a clock change, prescribing morning bright-light exposure to help realign circadian rhythms and lowering the threshold for check-ins with high-risk patients during the weeks around the transitions.

The authors argue that permanent standard time – rather than permanent daylight saving time – would better serve public mental health, as it more closely aligns with natural morning light exposure and human circadian biology.

“While more than 100 countries have observed daylight saving time sometime in the past, as of now, only about a third of the world follows this ritual, which offers little value to societal or economic well-being,” said Khubchandani, who has previously discussed this issue with several media outlets such as the BBC. “We could potentially continue to lose millions of dollars due to daylight saving time-related workplace injuries, traffic accidents, and health problems like heart attacks and strokes.”

To read the study, visit https://www.mdpi.com/2076-3425/16/5/522.

Carlos Carrillo López writes for New Mexico State University Marketing and Communications and can be reached at 575-646-1955, or by email at carlopez@nmsu.edu.