Daylight saving time harms health and increases inequalities

Abstract

Eliminating this structural barrier would help reduce sleep health inequity, write Karin Johnson and colleagues Daylight saving time, a seasonal hour shift in clock time, is a legislative policy followed by about 70 countries. In the spring clocks are set an hour later for daylight saving time and in the autumn they return to standard time, which more closely aligns to the sun being overhead at noon. Daylight saving time is harmful to sleep and health and disproportionately affects vulnerable populations.1 This practice should therefore be scrapped to try to reduce sleep disturbances and other health inequities.2 In recent years, greater scientific clarity has emerged regarding the public health harms of the biannual switching of the clocks,13 but people are split on whether to end clock change with permanent daylight saving time or permanent standard time. Some business leaders argue that evening light promotes economic activity so therefore argue in favour of permanent daylight saving time. They have used the harms of switching twice yearly4 and the promise of increased evening exercise to promote permanent daylight saving time as the healthy choice.5 The medical and scientific community, including the British Sleep Society, who issued a position statement on daylight saving time,4 support permanent standard time and advocate against permanent daylight saving time.13 Later sunrises and sunsets during daylight saving time are associated with increased rates of cancer,678 obesity,7 heart attacks,7 diabetes,7 suicide,9 and motor vehicle incidents,10 disproportionately affecting minoritised populations. …