It’s no surprise that issues like jet lag and shift work can have an incredibly detrimental effect on sleep, but what about Daylight Savings Time (DST)?
What is Daylight Savings Time?
This is the practice of turning clocks forward by an hour during the warmer months. Today, it’s implemented in more than 70 nations globally, including Australia (though not in all states), New Zealand, the United Kingdom, the European Union, Canada, and the USA. Its purpose is to advance the time at which darkness falls (and the sun rises in summer) and to better align waking hours with the hours of natural daylight.
In Australia’s states of NSW, Victoria, Tasmania, South Australia, and the ACT, clocks are turned forward by an hour on the first Sunday in October. They are turned back by an hour on the first Sunday in April. This means that one day in spring has just 23 hours, whereas one day in autumn has 25.
Why Do We Do This? Based on circadian rhythms, our daily schedules are naturally adjusted to sunlight; this is how ancient societies operated. With our modern Western clock-based society, however, during the summer months, the hours of daylight are not in sync with our regular “9-5” schedules. (In the middle of Australia’s summer, for example, dawn occurs quite early in the morning – at the summer solstice on December 21st, at Standard Time sunrise would be at 4.30 am). By advancing clocks by an hour over these months, sunrise occurs at a more convenient time to suit our wake-sleep schedules and it also provides more daylight hours for recreation after the workday has ended.
This practice of changing clocks forward for summer dates to the late 1700s when it was proposed by Benjamin Franklin to help economise on the use of candles. It wasn’t until 1908 that it was first implemented in Canada as an energy-saving measure, and it was adopted over time since then, most notably during wartime and then the energy crisis of the 1970s. It’s not used at all in Asia, Latin America, Africa, or the Caribbean, nor in the US states of Hawaii and Arizona (except for the Navajo Nation in Arizona).
While Daylight Savings Time (DST) is said to improve opportunities for health, lifestyle, and mental well-being with more “usable” daylight (as well as being economically beneficial), it is not universally enjoyed. Farmers (farming schedules are driven by dew and the readiness of dairy cattle to be milked; these are dictated by the sun), evening entertainment interests (e.g. outdoor cinemas and concerts, fireworks), and some religious groups (especially Jews and Muslims who may be required to pray or fast based on daylight hours) strongly oppose DST as being disruptive and inconvenient.
It also has distinct impacts on our sleep.
How Does Daylight Savings Time Effect Sleep?
Our bodies function on a natural sleep-wake cycle referred to as the circadian rhythm. This relies heavily on natural light and darkness as drivers of alertness and sleepiness. Standard Time better aligns with natural sleep-wake cycles.
It’s also important to understand that, despite popular belief, DST doesn’t give us “more” daylight – it simply shifts the timing of when we are awake during daylight versus darkness. (The driver of more daylight hours during summer and more hours of darkness in winter is the Earth’s seasonal tilt in relation to the sun – and this is the same regardless of how we set our clocks).
In terms of its impact on sleep, it’s commonly quoted that, whether a traveller across time zones or a person adjusting to DST, for each 1-hour of time change, it takes the body a day to adjust.
In reality, it can take much longer.
According to a Sleep Science and Practice Study, the transition to DST is associated with disturbed sleep schedules, acutely reduced sleep duration, and higher incidences of people experiencing restless, poor sleep quality. These effects lasted up to a week after clocks were turned forward.
Furthermore, if you are an “early bird” it can be harder to fall asleep when the sun has only just gone down (or is still up! – parents of young children will know exactly what we’re talking about!) During DST, we tend to go to bed (and sleep) later at night, translating to less sleep.
The American Academy of Sleep Medicine has gone so far as to support and recommend a change to permanent Standard Time – which better aligns with human circadian rhythms and would potentially translate to better public health and safety outcomes. Its research identified the following health and safety effects of the annual transition to DST:
- Increased incidence of atrial fibrillation leading to hospital admission
- Increased risk of heart attack and stroke
- Increased incidence of emergency department admissions
- Elevation in missed medical appointments
- Higher incidence of traffic accidents in the week following the transition to DST
- Associated mood disturbances
Those most vulnerable to these negative impacts of the transition to DST include teens, night shift workers, those who experience chronic sleep restriction during the school or work week, and people who struggle to sleep well while the sun is up.
How to Best Adjust to Daylight Savings Time
While we may assume that it’s quite easy to adjust to a one-hour clock change every six months, scientific data challenges this idea, especially with the transition to (as opposed to from) DST. Rather, it causes a cumulative effect of fragmented sleep and a longer time to fall asleep.
There are, however, ways to manage the transition and preserve your sleep quality:
- Try to be well-rested in the week or two before the DST transition.
- For a week or two before DST begins, go to bed 15 minutes earlier and increase this by 15 minutes every couple of days.
- Try not to sleep in on the day after the DST transition.
- On the first day after clocks go forward (i.e., in Australia, the first Sunday in October), take a 15-20 minute “power nap” in the early afternoon if you feel very sleepy.
- On an ongoing basis, commit to going to bed and waking up at the same time each day – this helps your body regulate sleep better.
- Maintain healthy sleep hygiene.
The good news is that, when we transition back to Standard Time in April, the extra hour of sleep we gain for a night can potentially (if temporarily) boost health and well-being. It also supports a healthier sleep schedule in line with natural light and darkness over the winter months. This demonstrably supports reduced risks of heart attack, stroke, sleep-related mood disorders and other health issues.
Stop Snoring to Sleep Better
Anything that helps promote better sleep will be helpful during this transition period and on an ongoing basis. If you or your partner snore (which is a proven disruptor of sleep), using SnoreMD can help.
By minimising issues like snoring, you give yourself the best opportunity to sleep well during the DST changeover and over the summer months. You also improve outcomes in terms of your cardiovascular health, memory, mood, metabolism, weight, immunity, and overall alertness and performance.
SnoreMD is the Australian brand of a globally renowned patented anti-snoring device. Safe for adults to use, this comfortable and micro-adjustable mouthguard gently moves the lower jaw very slightly forward during sleep. This effectively opens the airways of the mouth and throat, preventing snoring and enhancing breathing function. It’s an easy, affordable, reusable option for almost everyone.