Workers can experience somewhat higher risks to both their health and safety after a time change. According to the Centers for Disease Control and Prevention (CDC), it can take about one week for the body to adjust the new times for sleeping, eating, and activity. Until they have adjusted, people can have trouble falling asleep, staying asleep, and waking up at the right time.
This can lead to sleep deprivation and reduction in performance, increasing the risk for mistakes including vehicle crashes. A 2015 study reported men and persons with heart disease may be at higher risk for a heart attack during the week after time changes.
The reason for these problems is thought to be disruption to circadian rhythms and sleep. Circadian rhythms are daily cycles of numerous hormones and other body functions that prepare us for the expected times for sleeping, eating, and activity. Circadian rhythms have difficulty adjusting to an abrupt one hour time change.
CDC recommends gradually move the timing of wakening and bedtime, meals, exercise, and exposure to light by 15 – 20 minutes later each day starting about three days before the time change until these are in line with the new time. About 1 hour after awakening in the morning, you can keep the lights dim and avoid electronic screens to help the body move to a later time that it is ready to wake up in the morning–and go to sleep at night.