There is reason to be excited by Daylight Saving changes, with longer daylight hours to enjoy on summer nights and an extra hour’s sleep when clocks are turned back, but there are also possible negative impacts to our health.

When does Daylight Saving start and end?

Daylight Saving Time^[1] begins at 2am on the first Sunday in October, when clocks are put forward one hour. It finishes at 2am (which is 3am Daylight Saving Time) on the first Sunday in April, when clocks are put back one hour.⁽¹⁾

Our Body Clock and Daylight Saving

Our circadian rhythms (our internal body clock) are timed to match the environments cycle of light and darkness. As we go into the start of Daylight Saving our body suddenly needs to wake up when it is programmed to be asleep.

At the end of Daylight Saving in Autumn (April), when the clocks are put back one hour, we have the joy of an extra hour that night. Thanks to the extra hour, this isn’t anywhere near as disruptive to our bodies as the loss of an hour. It usually takes only one night for our body to get used to the ‘going back’ compared to around a week when Daylight Saving begins.

How important is sleep?

A loss of one hour might not seem much, however this can affect our performance the next day as we may not be as alert. US study^[2] found the number of traffic accidents after the loss of one hour to be higher⁽²⁾. However, if you adjust your bedtime earlier for three or four nights before the Spring Daylight Savings transition, you will reduce the impact of sleep loss, and be less susceptible to sleepiness the following day.

Tips for a good night’s sleep

We know that sleep is the time our body needs to restore. To get a good night’s sleep at any time of the year, here are some tips from the Sleep Health Foundation^[3]:

1. Make the bedroom as bright as possible when you first wake up in the morning.
2. Eat a good breakfast, it signals the start of the day to the body.
3. Go outside in the sunlight in the early mornings.
4. Exercise outside in the mornings.
5. Try to get between seven to nine hours sleep each night.
6. Don’t drink coffee, tea or other caffeine drinks in the evening,
7. Avoid smoking just before bed or during the night.
8. Don’t go to bed hungry or too soon after eating a large meal.
9. Make the bedroom cool to sleep in as your body temperature drops before bed.
10. Have the bedroom dark at sleep time to help with melatonin production, the hormone that helps you sleep.

We can all enjoy the Daylight Saving time changes and minimise impact on our health if we plan ahead. Start going to bed a little earlier and getting up earlier a week or so before it begins. Then when we change back, it is already getting darker earlier in the evening, to help us go to bed earlier and let our bodies enjoy enough sleep.

References:

1. https://www.sleephealthfoundation.org.au/files/Daylight_Saving/Daylight_Saving_and_Sleep-0319.pdf
2. Jason Varughese, Richard P Allen, Fatal accidents following changes in daylight savings time: the American experience, Sleep Medicine, Volume 2, Issue 1, 2001, Pages 31-36, ISSN 1389-9457, https://doi.org/10.1016/S1389-9457(00)00032-0.
3. https://www.sleephealthfoundation.org.au/daylight-saving-2.html