A major review of studies has warned that daylight saving time may pose serious risks to people living with chronic mental illnesses. The practice of advancing clocks by one hour in spring and returning to standard time in autumn affects the body's natural circadian rhythm, with implications for nearly one billion people worldwide.
Researchers from New Mexico State University compiled findings from 60 studies across psychiatry, neuroscience and public health. They found that the one-hour time shift acts as a population-wide circadian stressor, particularly harming those with depression, bipolar disorder, anxiety disorders, PTSD, ADHD and psychotic disorders.
“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, assistant professor of public health at NMSU. Study co-author Kavita Batra added: “For millions living with chronic mental illness, this is more than lost sleep; it may represent a preventable public health risk.”
The review, published in the journal Brain Sciences, noted that spring transitions are associated with increased sleep disturbance, impaired executive functioning, reduced attention and working memory, heightened emotional reactivity, and elevated risk of manic episodes. Scientists urge clinicians to treat DST transitions as modifiable risk windows, advising patients to gradually shift sleep schedules and use morning bright-light exposure.
Researchers advocate for permanent standard time rather than permanent daylight saving time, as it aligns better with natural morning light and the body's internal clock. “We could potentially continue to lose millions of dollars due to daylight saving time-related workplace injuries, traffic accidents, and health problems,” said Jagdish Khubchandani, another author of the study.
