Daylight saving time is often viewed as a minor inconvenience. Twice a year, millions of people adjust their clocks by one hour and then spend a few days getting used to the new schedule.
Many people complain about feeling tired or losing sleep, but a growing body of research suggests that the effects may be much more serious than simple grogginess.
A major new study by researchers from New Mexico State University and the University of Nevada, Las Vegas has found that daylight saving time may create significant challenges for mental health.
The study, published in the journal Brain Sciences, reviewed more than 60 scientific studies from around the world. These studies covered fields such as sleep science, psychiatry, neuroscience, and public health.
The researchers concluded that the one-hour clock change acts as a widespread stressor for the body’s internal clock, also known as the circadian rhythm.
This biological clock helps regulate sleep, alertness, hormone production, mood, body temperature, and many other important functions. When the clock is suddenly shifted by an hour, the body often struggles to adjust.
For many healthy people, the adjustment may take several days. However, for people living with mental health conditions, the effects may be much stronger.
The researchers found evidence that individuals with depression, bipolar disorder, anxiety disorders, post-traumatic stress disorder, attention deficit hyperactivity disorder, and psychotic disorders may face greater risks during the days and weeks after a clock change.
The body’s circadian rhythm is strongly influenced by sunlight. Morning light plays an especially important role in helping the brain know when to wake up and when to sleep. When clocks suddenly change, the timing of light exposure changes as well. This can confuse the body’s natural rhythms and disrupt sleep patterns.
Sleep problems are already common among people with mental health conditions. Many psychiatric disorders are closely linked to disturbances in sleep and circadian rhythms. As a result, even a one-hour shift can worsen existing symptoms. Some people may experience greater anxiety, lower mood, difficulty concentrating, irritability, or worsening psychiatric symptoms.
The researchers argue that daylight saving time should not be viewed simply as a scheduling issue. Instead, it should be recognized as a predictable period of increased health risk. They suggest that healthcare providers may be able to help patients prepare for these transitions in advance.
One recommendation is gradually adjusting sleep schedules several days before the clock change. Going to bed and waking up slightly earlier or later before the transition may reduce the shock to the body’s internal clock. Morning exposure to bright light may also help the brain adapt more quickly to the new schedule.
The study also suggests that healthcare providers should consider additional check-ins with patients who are particularly vulnerable during the weeks surrounding daylight saving time transitions. Because the risk period is predictable, preventative steps may help reduce negative outcomes.
The findings arrive during an ongoing debate about whether seasonal clock changes should continue. Supporters of ending daylight saving time argue that the practice provides few modern benefits while creating significant health and safety concerns.
Previous studies have linked clock changes to increased risks of traffic accidents, workplace injuries, heart attacks, and strokes.
The researchers believe that permanent standard time would be a better option than permanent daylight saving time. Standard time more closely follows natural patterns of sunlight and aligns better with human biology.
According to the authors, maintaining a schedule that matches natural morning light may help support healthier sleep and mental well-being.
If you care about depression, please read studies about how dairy foods may influence depression risk, and B vitamins could help prevent depression and anxiety.
For more information about mental health, please see recent studies that ultra-processed foods may make you feel depressed, and extra-virgin olive oil could reduce depression symptoms.
Source: New Mexico State University.
