As Americans prepare to set their clocks forward for daylight saving time this weekend, new research from California scientists suggests the annual time change may have hidden health consequences, including triggering migraines and reducing restorative deep sleep.
The study, conducted by researchers at UC Davis Health, monitored nearly two dozen participants before and after the clocks sprang forward in March 2023. Using mattress sensors and daily diaries, the team tracked sleep patterns and headache frequency. They found that the number of days participants experienced migraines rose from one week to nearly two weeks following the time change, while deep sleep decreased by an average of 10 minutes per night.
“We know that clock transitions are not good for brain health,” said Dr. Sasikanth Gorantla, a neurologist and sleep expert at UC Davis Health. “But the exact impact was understudied—especially when it comes to how it affects headaches and migraines.” More than 35 million Americans suffer from migraines, with women three times more likely to be affected due to fluctuating hormone levels.
The researchers believe the loss of deep sleep impairs the brain's ability to clear metabolic waste, potentially triggering migraines. Previous studies have linked daylight saving time to disruptions in the sleep-wake cycle. “Our findings show that even a small disruption to the body’s internal clock can have an impact on people living with migraines,” Gorantla added.
To mitigate these effects, Gorantla recommends gradually adjusting sleep schedules by going to bed 15 minutes earlier each day, limiting caffeine, avoiding naps, exercising during the day, and reducing exposure to light and technology at night. Morning daylight and afternoon walks can also help synchronise the body’s internal clock. The American Academy of Sleep Medicine advocates for year-round standard time to better support circadian alignment and overall health.
