Around a third of the world observes daylight saving time (DST), and for many Australians, this includes you.
Daylight saving will start at 2am on 6 October.
Here's everything you need to know about daylight savings and how it affects you.
Do clocks go forward or backwards?
At 2am (AEST) on Sunday, some clocks will turn forward one hour to 3am as DST comes into effect for a majority of Australians.
If you live in NSW, Victoria, the ACT, South Australia or Tasmania, you will be losing one hour on Sunday morning.
Supporters of DST believe it is a worthwhile trade-off, as waking up later in the day means you get additional hours of natural sunlight.
Professor Tim Bedding from the School of Physics at the University of Sydney explained that the tilt of the Earth's axis means the time between sunrise and sunset shifts throughout the year.
"The result is that days are longer in summer than in winter," he said.
Which Australian states and territories do not observe DST?
Over the past 50 years several Australian jurisdictions have voted for or against daylight savings for their region.
Bedding said geography is a key factor in decision-making.
"The effect of DST becomes less as you move towards the equator, which is presumably why Queensland decided not to adopt daylight saving."
Along with Queensland, Western Australia and the Northern Territory have also rejected DST.
"In a large geographically and climatically diverse country, one size does not necessarily fit all and should not be imposed upon all," Bedding said.
Will daylight savings make you sick?
There is ongoing debate around whether the time change impacts health.
Weight loss expert Dr Nick Fuller from the Charles Perkins Centre said the loss of an hour creates a misalignment in a person's internal biological clock.
"This is a temporary effect, but when it comes to food, you may find yourself eating later in the evening and doing other activities to fill the daylight hours," he said.
"If you eat close to bedtime, it can acerbate problems with digestion and reflux, worsening your sleep."
Do you lose sleep in daylight savings?
Professor Leon Lack, a sleep expert from Flinders University, said there is no significant evidence that DST impairs sleep or daytime functioning.
"We found that those who live in states that observe DST tended to go to bed and wake up later compared to those in regions that stay on standard time," he said.
Reece Kemp, another sleep expert and Lack's research associate said: "Research suggests that even if the initial transition into DST may present challenges, any negative effects appear to subside within one to three months at the most."
While many Australians will not feel a notable change in their health, people predisposed to conditions like insomnia or acid reflux could experience discomfort.
Tips from the experts
If you have difficulty with fatigue or sleep-related issues, Lack, Fuller, and Kemp have some advice.
- Start your day with sunlight: Each morning leading up to and after the DST transition, get outside for some morning sunlight.
- Limit afternoon caffeine: Enjoy your morning tea or coffee, but avoid caffeine after midday to prevent it from keeping you up at night.
- Eat a healthy breakfast early: Kickstart your metabolism and set your body clock by eating breakfast first thing in the morning. This can help reinforce your wake-up time.
- Take your regular exercise, but not too late: Regular physical activity can promote better sleep, but avoid vigorous workouts late in the evening to ensure they do not interfere with your bedtime.
- Reduce screen time before bed by keeping technology out of the bedroom and dimming the lights two to three hours before sleep to support your natural circadian rhythm.
- Plan for post-DST rest: Expect some sleep disruption after the clock change. Do not overload your schedule on Sunday or Monday, and if needed, take a brief (15-minute) power nap around lunchtime to recharge.
