Everyone knows the importance of sleep and how a lack of it can impact your routine. Not only does it help you feel awake to get through your day, but it’s also important for your health and wellbeing1. Sleep also helps with learning and the formation of your long-term memories. A lack of it can lead to more problems like difficulty focusing and thinking clearly¹. 

However, despite how important it is, most people will experience sleep problems at some point in their life. Whether you’re tossing or turning, struggling to switch off or have a diagnosed sleep disorder, you’re not alone. In fact, around 2 in 3 Australian adults have reported at least one sleep problem, with 48% reporting at least two². Issues with sleep can lead to fatigue, irritability, moodiness and even sleep disorders².

So, how do you fix it? You may have heard about the circadian rhythm, a key function in your ability to fall and stay asleep. Let’s take a closer look at the circadian rhythm, how it impacts your sleep and what to do about it. 

What is the circadian rhythm? 

Circadian rhythm, meaning how your body naturally regulates its mental state and behaviour, is most commonly known as your 24-hour sleep-wake cycle³. Simply put, it’s our internal clock that regulates how alert and sleepy we feel throughout the day. 

There are a handful of things that can throw off your circadian rhythm including⁴:

• Jet lag
• Shift work
• Irregular sleep patterns
• Artificial lighting
• Caffeine
• Stress

The good news is that you can maintain your circadian rhythm. By keeping your sleep routine consistent, as well as practising good sleep hygiene habits, you can align your sleep-wake cycle with your natural body timing³. 

What happens when circadian rhythms are disrupted? 

When your circadian rhythm is disrupted, you may find yourself feeling tired throughout the day, less alert, or having problems with your memory or making decisions⁵. Some disruptions to your sleep like jetlag and work can be temporary and easily fixed. However, long-term disruptions that are caused by ageing, your genes or a medical condition can become a longer-term issue, which is where you might need help to find your natural rhythm once more⁶. 

Recent studies have also found links between your natural sleep-wake cycle and mood regulation or disorders, which can increase some symptoms in affected people⁶. 

How do you know if your circadian rhythm is off?

While a disrupted sleep schedule is an obvious sign your circadian rhythm is off, there are some other symptoms to keep an eye out for. Some of the top signs to know your circadian rhythm is off include:^7,5

• Having trouble falling asleep.
• Finding it difficult to stay asleep, or falling back to sleep in the middle of the night or early in the morning.
• Waking up earlier than you intend to.
• Struggling to wake up or waking up at irregular times every day.
• Experiencing daytime sleepiness or fatigue.
• Needing to nap during the day.
• Getting headaches.
• Feeling depressed or irritable.
• Noticing a lack of alertness.
• Having trouble making decisions or with memory.

Keep in mind, experiencing these issues once in a while may be normal. However, if they are becoming a weekly or more common occurrence, it may be a sign your circadian rhythm is off.

Can you fix your sleep wake cycle?

The good news is that you can take steps towards fixing your sleep-wake cycle. Forming good habits and routines are key to giving your circadian rhythm a helping hand. This means setting yourself and your bedroom up for good sleep hygiene. Some things you can try to help improve your sleep include: 

• Minimising light
• Reducing screen time in the hours leading up to sleep
• Setting up your bedroom sleep environment by considering things like noise, light and temperature
• Limiting physical activity before bed 
• Reducing alcohol and caffeine in the afternoon and evening
• It’s also best to also avoid naps or staying up late to try and make yourself sleepy, as irregular sleep can further hinder your sleep wake cycle⁴. 

How to fix your circadian rhythm with light 

Light plays a big role in signalling your body when it should be up and active, and when you should be asleep. It can also affect the production of melatonin, a sleep-inducing hormone⁸. This makes light a powerful tool for resetting your circadian rhythm.

One of the best ways to use light is by exposing yourself to sunlight in the morning, and limiting exposure at night time⁸. Research has shown light in the evening, around 2 hours before and after your usual bedtime, can cause your circadian system to delay by 2 hours, while light around an hour before and after your normal waking time can shift this two hours earlier⁹. Light can even filter through your closed eyelids, so can be used in your favour, if needed⁹. 

Circadian rhythm lighting can also be created artificially, such as using warm light similar to the setting sun to help tell your body it's nearly time for sleep¹⁰.  However, bright or cool-toned lights, such as blue lights from screens can make you more alert before bed¹⁰. Just 2 hours of exposure to blue lights, like your phone or TV before bed can significantly decrease your melatonin levels needed to get a good night’s rest¹¹. 

For someone wanting to try to wake up earlier, get some natural sunlight in the hour after your wake to help you rise earlier¹². If you want to stay up later, you can use exposure to cool-toned lights to stop you feeling tired early in the evenings¹². Light therapy treatments may also help if you are suffering from jet lag or other sleep problems¹³.

How to reset your circadian rhythm through nutrition 

Another way to help reset circadian rhythm sleep cycles is through your nutrition. This is because what you eat and drink, as well as your metabolism and health, are all connected to your circadian rhythm¹⁴. 

Your nutrition can also impact your cortisol and melatonin levels, which can stimulate different hormonal responses¹⁵. Some studies suggest that eating within 3 hours of bedtime can actually lead to difficulty falling and staying asleep¹⁶. This is also the same for caffeine. 400mg of caffeine (such as that in around 4 cups of coffee, or also found in green and black tea, and soft drinks) within 6 hours of bedtime can disrupt sleep by up to one hour, which may not seem like a lot, but over multiple days, can lead to concentration issues throughout the day¹⁷.

However, some foods like bananas, avocados and certain supplements are all high in magnesium, which has been found to affect melatonin levels¹⁸. Valerian root supplements may also help make falling asleep easier and increase time in the deep sleep stage¹⁹. For improved sleep quality and even potentially a better mood when awakening, saffron supplementation may have some effect on the circadian rhythm²⁰.

How long does it take to reset your circadian rhythm?

The length that it takes to reset your circadian rhythm depends on what disturbed it in the first place. If you’ve been travelling and experiencing jet lag, it may take several days to reset your natural sleep-wake cycle⁶. For every timezone you cross, expect your circadian rhythm to take 1 to 1.5 days to adjust²¹. However, for other disruptions like a sleep disorder, or stress, it can take even longer. 

Generally, research suggests that for every one hour of sleep you lose, it can take up to four hours to recover, and up to nine days to completely pay back your sleep debt²². Remember, forming good habits and bedtime routines can help you fix your circadian rhythm, so the sooner you start, the sooner you’ll likely be back to your normal sleep routine⁴. 

Circadian rhythm: sleep techniques

The best way to look after your circadian rhythm is by forming good sleep habits³. While following sleep hygiene guidelines will help you find your natural sleep and wake rhythms³, there are many habits you can add to your bedtime routine. Whether you love the idea of unwinding with a warm bath, or prefer to stay out of bed unless you’re sleeping, there are plenty of things you can try. 

For more tips on forming good sleep habits or other bedtime tips, the Swisse Wellness Hub has plenty of information for you to explore. Check out some of our top sleep tips from our Swisse Sleep Squad or learn more about how saffron is linked to better sleep.

References:

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