Daylight Saving: How Switching Our Clocks Forward Affects Our Health

Bringing your clock forward an hour to switch over to daylight saving has surprising impacts on our health -- both good and bad -- according to experts.

In the early hours of Sunday morning, most Australian states switched their clocks forward an hour, causing us all to get an hour less of sleep.

But it’s not just our clocks that are adjusting to the change, our body has to work extra hard to make up for the loss of sleep.

Changing our clocks causes a temporary state of misalignment in our body’s natural clock caused by fluxes in melatonin -- the hormone that regulates our sleep. But the evidence is divided on whether this disruption is good or bad for our health.

READ MORE: How To Prepare Yourself For Daylight Saving


While these biological changes leave us feeling weary and impact our ability to think clearly, they have also been found to have some more sinister effects, such as increasing our risk of heart attacks.

But Professor Dorothy Bruck, a sleep expert from the Sleep Health Foundation, said that the health impacts of daylight saving are mainly the acute and harmless effects felt in the days following the change.

“The normal affect you would see is less concentration, less attentiveness, grumpiness, feeling sleepy after our lunchtime meal. This usually takes a few days to settle down and some people adjust better than others," Bruck told ten daily.

But this seemingly harmless loss of sleep also comes with risks, with some research suggesting that the risk of car accidents increases in the period following daylight savings.

But according to Bruck, the data is “pretty messy” on whether there is in fact an increased risk of car accidents as a result of sleep deprivation, with some research showing an increased risk when we oversleep.

Nonetheless, people should be weary on the roads in the days following the switch, particularly if we are feeling weary, Bruck said.

“Usually we say to people be a little more careful with driving if we are feeling more sleep deprived. Most of this will happen on a Monday morning, usually when the crunch comes," she said.

Heart attack risk 

As for whether the change can have more severe and even fatal impacts on our health – the research is also divided, according to Bruck.

While some research has indicated that our risk of heart attack increases in the period following the time change, other research suggests the opposite, she said.

“Studies that show those things get the headlines but if we look deeper it’s a much more complicated picture," she said.

Boosting mood

But it’s not all doom and gloom, with the switch in rhythm also having an array of benefits for our overall wellbeing.

According to Bruck, daylight saving actually helps our circadian rhythm,  by increasing our exposure to daylight which in turn promotes better quality sleep by suppressing melatonin throughout the day.

“It helps to build a robust circadian rhythm, high in the day and low at night and that’s always a good thing," she said.

This has beneficial effects on our overall wellbeing including socially and for our mental health.

“We know mental health has strong ties with the quality of sleep you’re getting. Good quality sleep will mean you’re less grumpy, irritable and less sad," Bruck said.

It’s these beneficial effects that make daylight savings “worth” the couple of days of sleep disruption, she added.

And for those feeling the lack of sleep on Sunday, the best thing to do is to maximise your exposure to natural light.

“Early morning light is good. As soon as Monday morning comes light in, if it’s a good day like today, have breakfast outside," Bruck said.

"Those things will help you adjust.”