What happens to our brain while we sleep?
In the first episode of our new video series, the Sleep Wisdom, Dr Rebecca Robbins helps us debunk the myth that during sleep our brain is completely switched off.

Earlier this summer we launched a new video series, titled the ‘Sleep Wisdom‘. Each episode aims to debunk common sleep myths, and bring the science of sleep to the forefront. In our first episode, Sleep Expert to Savoir, Dr Rebecca Robbins, explains what happens to our brain while we sleep – from processing memories to brain detoxification and its importance to our health and well-being. Join us as Dr Robbins uncovers the science of a restorative night’s rest.
It is a myth that during sleep our brain is switched off and resting. Instead, our brain goes in and out of one of four different stages. And in this beautiful, rhythmic fashion.


“As we start to enter sleep at night, the pens of the electrodes – if I were measuring you in our sleep laboratory, start to slow. Indicating that our brain is starting to slip into some of the lighter stages of sleep. During the lighter stages of sleep, we’re easily awoken by sounds around us. But as we start to slip into some of the deeper stages of sleep at night, the pens of the electrodes, if we’re monitoring you in the laboratory, start to slow so much, that it sounds as though there is absolutely nothing happening in the brain. Now, this is essential. Because this is where, we as humans, come the closest to hibernation in our typical day.
Then, something fascinating happens. After about 20 minutes from falling asleep, we enter our first rapid eye movement period of the night. This rapid eye movement period lasts for a very short time, but during REM the brain becomes alive. If I were monitoring you in my laboratory, the pens of the electrodes would show enormous activity in the brain. There are very high frequencies that are quick brainwaves, and very low amplitude. That’s the space from peak to trough in a brainwave. Indicating a tremendous amount of activity.
And what’s so fascinating, is that patterns of wakefulness, when we’re learning new activities, in the brain, are actually repeated during sleep
During this stage of sleep, what’s happening in the brain is we are repeating and rehearsing some of the events from our day before. And what’s so fascinating, is that patterns of wakefulness, when we’re learning new activities, in the brain, are actually repeated during sleep.
So, this stage of sleep is important for our cognitive function, our memory and so many areas of our brain. One of the most fascinating areas of sleep science is indicating that during sleep compared to wakefulness, we experience an accelerated clearance of brain toxins. That clearance happens at about a 60% greater rate during sleep than wakefulness. And that removal of toxic particles is vitally important for us to maintain a healthy brain – today, tomorrow and well into the future.
We see in our epidemiological studies that when we’re not getting enough sleep and getting the benefits of all that clearance of these dangerous brain toxins, over time, we’re at increased risk for Alzheimer’s disease and dementia. So, it is a myth that our brain is switched off and resting during sleep. Instead, we enter and re-enter these different beautiful stages of sleep in a symphonic pattern. And we must hit each note in the symphony of the night to wake up and be at our best.”
Dr Rebecca Robbins
Join us on Instagram and enjoy all episodes of Sleep Wisdom, debunking common sleep myths, discovering the science of sleep and more.
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Everything you need to know about insomnia
Introducing our new series, Sleep Matters, where we dive into sleep problems some of you may experience and discover solutions that’ll bring you a lifetime of restorative sleep. In our first issue, we uncover everything you need to know about insomnia and its effects.

While many elements contribute to enjoying a good night’s rest, for some, there are concerns that good sleep hygiene and bedtime routines simply can’t fix. The effects of inadequate sleep can be detrimental to your health. Affecting next-day performance, causing irritability, and compromising your immune system.
Recent research shows that 10% of the worldwide population struggles with insomnia. Additionally, t’s estimated that 35% of people will experience symptoms of insomnia it at some point in their lifetime. Although for most, these symptoms can ease over time, there are others, who’ll experience long-term effects of the disorder.
To understand more, we sit down with Sleep Expert Dr Rebecca Robbins. And together, we uncover everything you need to know about insomnia, the science behind sleep problems and discover how we can tackle their effects so that we can truly enjoy a restorative night’s rest.

What are the tell-tale symptoms of insomnia?
According to the American Academy of Sleep Medicine, insomnia is a clinical diagnosis. It’s defined as the subjective perception of difficulty with sleep initiation, duration, consolidation, or quality that occurs despite adequate opportunity for sleep and results in daytime impairment. Insomnia becomes chronic when a person begins having difficulty falling asleep or staying asleep for as little as three nights per week for at least two consecutive weeks up to three months.
Dr Robbins: So, if you find it difficult to get the rest you need despite giving yourself sufficient time to sleep, it might be time to speak to a health professional, who can diagnose you.
What are the most common causes of insomnia?
Dr Robbins: There are many causes of insomnia, ranging from physical, such as hormonal fluctuations, injuries or pain. Psychological causes such as depression and anxiety, and situational, such as when we experience jetlag.
We all can likely relate to the experience of insomnia symptoms at one time or another in our lives. The truth is, sleep is the result of our waking days. This can include stressful events like frustrating professional or personal experiences. All of these can limit our ability to fall asleep or maintain sleep.
The truth is, sleep is the result of our waking days.
Is there a link between circadian rhythm and insomnia?
Dr Robbins: Circadian rhythm disorder symptoms are similar to those of insomnia. They can include difficulty falling, staying asleep or waking up too early.
However, symptoms of the former are due to a disruption in the timing of sleep, which can be caused by irregular sleeping times, inadequate time in the daylight and poor diet. Whereas an individual suffering from insomnia can experience all the symptoms even if they practise healthy sleep hygiene.


Are there any groups of people who are more likely to be at risk of insomnia?
Dr Robbins: There are a few groups that are at greater risk of insomnia. Unfortunately, sleep systems decline with age, making it more difficult to fall asleep and consolidate sleep. For these reasons, insomnia is more likely among older adults than younger adults. However, individuals with family history of insomnia and those that are prone to stress and worry are also at greater risk. There are certain medical and psychiatric disorders, such as heart disease, asthma, anxiety, and depression that can make an individual more likely to experience insomnia too.
What are the consequences of untreated insomnia?
Dr Robbins: Untreated insomnia can present short consequences, including irritability, feelings of anxiety and depression. It can also affect our immune system and increase the risk of colds and flu. There is also research that estimates the costs of untreated insomnia to be as high as $100 billion US dollars per year. This is due to additional healthcare costs, reduced productivity, and accidents.
Concerningly, in the longer term, including increased risk for chronic conditions, such as cardiovascular disease and obesity. There is also evidence that untreated insomnia could place older adults at an increased risk of dementia and Alzheimer’s disease, therefore, underscoring the importance of being treated.
How does insomnia affect our mental and physical well-being?
Dr Robbins: Those suffering from insomnia can face myriad challenges to their mental and physical well-being and performance. Untreated insomnia presents risks for brain fog and lower productivity, shorter attention span, and less creative problem-solving. An individual may also experience increased feelings of anxiety, which can greatly affect both their personal and professional life.

We’re more aware of our well-being and the importance sleep plays in this. Does this mean there are fewer people suffering from insomnia than before the COVID-19 pandemic?
Dr Robbins: We do have evidence that symptoms of insomnia increased in prevalence across the globe amidst the COVID-19 pandemic, which was marked by conditions ripe for insomnia, including tremendous uncertainty and unknown.
What can someone do to manage the symptoms of insomnia?
Dr Robbins: Fortunately, there is a range of treatments for insomnia. These include both pharmacological interventions as well as behavioural treatments. Excitedly, research shows that these two pathways are both highly efficacious for attenuating insomnia symptoms and improving quality of life.
On the behavioural side, the gold standard treatment is called “Cognitive Behavioural Therapy for Insomnia” and includes specific recommendations to help the person suffering from insomnia to reframe how they think about sleep and their bedroom. Another central piece of CBTI is relaxation training and learning meditation and mindfulness exercises to ease tension around bedtime.
Untreated insomnia presents risks for brain fog and lower productivity, shorter attention span, and less creative problem-solving.
Lastly, are there any precautions we can take to prevent insomnia?
Dr Robbins: There are a handful of precautions we can all take. Following a healthy diet and exercising regularly can greatly impact an individual’s likelihood to experience insomnia. You should also introduce a consistent sleeping routine, spend an adequate amount of time in the daylight and outdoors and avoid alcohol and caffeine after 2pm.
If the symptoms of insomnia sound like something you are experiencing, we recommend reaching out to a Sleep Specialist, who can assist you further and recommend the right treatment for you.
Dr Robbins is Assistant Professor in Medicine at Harvard Medical School and an Associate Scientist at the Brigham and Women’s Hospital and has been an expert on the science of sleep for Savoir since 2020.
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Beauty, sleep, and circadian rhythm with ByNACHT founder Jessica Hoyer
It was only a matter of time – and perhaps the right person, to bring beauty into the world of sleep. Inspired by her own experience with poor-quality sleep, ByNACHT founder, Jessica Hoyer, explores the connection between beauty, sleep, and circadian rhythm.

As experts in handcrafting the world’s finest beds, we are committed to discovering the ingredients that make up a restorative night’s rest. Throughout this journey, we have met some of the most esteemed individuals within the wellness space. Bringing together their knowledge, science and curiosity, these experts challenge the common perception of sleep and aim to provide modern-day solutions that deliver a lifetime of quality sleep.
Driven by her own experience with lack of sleep, Jessica Hoyer embarked on understanding the connection between science, aromatherapy, and sleep. Combining cutting-edge technology with insight from world-leading sleep experts, she created a brand that makes our sleeping routines all that more luxurious.
With a curated range of creams, serums, and balms, ByNACHT (German for ‘By night’), provides key ingredients to a wholesome sleeping routine. Today, we sit down with Jessica Hoyer, who talks us through what inspired her journey and how her findings influence her approach to beauty sleep.


I wanted a concept and products that were wholesome, yet cutting-edge in ingredients and something that didn’t fall short in all aspects of the lines I used to buy.
Savoir: Is ByNACHT inspired by your own experience with lack of sleep?
Jessica Hoyer: Yes, ByNACHT was literally born out of my own sleepless nights. Before I started the brand, I had my own advertising agency and was working for big international clients and frequently flying around the world for work. I was constantly jet-lagged, exhausted, and looked – and felt dull. My mother (a certified aromatherapist) mixed me the ‘sleeping balm’, which is still a bestseller and the original recipe as of today, and I finally had a good night’s sleep.
Now, I was looking to find a skincare that helped with me looking dull. I wanted a concept and products that were wholesome, yet cutting-edge in ingredients and something that didn’t fall short in all aspects of the lines I used to buy. And there wasn’t a cure for it in the current skincare market. I didn’t find anything that was closing the gap between the scientific findings around sleep being a catalyst for great skin. When I started looking into studies I was immediately fascinated and knew I had found something very special.
What’s driven you to explore the connection between circadian rhythm, sleep, and beauty?
I have never intended to be a part of the beauty industry but created my brand out of my own passion after reading all the studies and mostly my need to find something that is science-based and holistic in the approach to combine sleep and skin. Because these scientific studies and findings all state that sleep quality impacts skin function and ageing.
In terms of science, my biggest learning was that every single study and scientific research facts and findings say that skin renewal, wound healing, growth hormones, collagen production, fibroblast renewal and overall turn-cell over and really, basically everything else that is needed for amazing skin are ONLY happening at night.
As for wound healing, it was mind-blowing to see what the right ingredients (at this time it was our ultra-repair serum) and a good night’s sleep can do for your skin. And those scientific facts were, and still are my biggest guidance when creating a new product.

How did your findings inform your approach to sleep and beauty?
Skin never sleeps and that is probably the most interesting research finding ever. During the day, your skin is in a protective state, warding off elements such as sun damage or oxidation. While at night, your skin goes into renewal mode, regenerating new skin cells and cycling oxygen and nutrients.
Our skin has its own circadian clock. Different skin processes occur at different times according to this internal schedule. Night time is prime time for repairing damage and rebuilding cells and tissues, and cell renewal is up to 8 times higher. Collagen production and Growth hormone (HGH) production are at a peak which in turn accelerates skin regeneration and the production of antioxidant enzymes.
The bottom line is – support your skin at night with the right products and you will see a dramatic difference in your complexion by day.
What is your current bedtime routine and how do you maintain it when travelling?
The time before going to bed is my ‘me-time’ and whether I have 10 or 30 minutes, I never skip cleansing my face and applying my skincare. I combine this with my relaxing playlist and write down every single ‘to-do’ and thought in a little notebook, so my head is clear when I go to sleep.
That is a game-changer really, so I feel well-prepared for the next day, and nothing gets lost when I have my morning coffee. This routine is something I really stick to, even when I am travelling because I found it to make such a difference the next morning in terms of how I look and feel. I also always bring our mini travel sizes with me when I’m away.
What’s the one luxury you can’t live without?
I think a lot of people would expect me to say that my biggest luxury is sleep now, but for me, sleep is a necessity and vital for my well-being and overall health. I have learned so much about the importance of a good night’s sleep that I treat it as a priority. So, I will go with time with my son, as this is really the thing that means the most to me and no amount of money, work or opportunity could make me compromise or minimize that time.

For those unfamiliar with ByNACHT, is there one product you recommend starting with?
Ohh, that’s a hard question as I love all of our products but I personally would say our Hypercharged Glass Skin Serum (a worldwide and award-winning bestseller we can’t keep in stock for long until sold out) that features an outstanding combination of eight different Hyaluronic acids and an unmatched combination of 13 different active botanical extracts.
I would go as far as to say that if you have ever tried it, you will never go back to an ‘ordinary’ Hyaluronic Serum ever again. It is that good. And then there is of course our original – the Sleeping Balm. It always works and thousands of raving customers can’t lie. You will sleep.
Do we need a different approach to skincare at night, than we do during the day?
Yes, absolutely and in so many aspects – from the quality and components of ingredients to the sheer quantity we use. We need a lot more active ingredients at night in order to wake up with the best skin because of the skin being so active at night and some other factors like trans epidermal water loss. At night, the skin’s cells regenerate fastest due to the increased blood flow to the skin. If you use effective products, your skin can maximize its rejuvenation with serums and creams that help the skin renew itself.
And for that, we need to have a night-time skincare line that is addressing skin issues before the regenerative process of sleep begins. So, ByNACHT products are designed very differently, you will see a difference within one night already. I strongly believe that high quality and efficacy will always come through.
At night, the skin’s cells regenerate fastest due to the increased blood flow to the skin. If you use effective products, your skin can maximize its rejuvenation with serums and creams that help the skin renew itself.
And lastly, what is your advice for achieving a restorative night’s rest?
My advice would be to invest in making your bedroom a sanctuary and a place where you really just rest. I never work or use my laptop in bed but make sure I keep a book and a pen nearby to write done any wandering thoughts before sleep.
Investing in a high quality bed is also vital. We spend a lot of time in our beds and for me, that is the most important piece of furniture in my house.
I also stick to the common rules, such as no phone before sleep, having a colder room temperature and if I am very exhausted, I take a warm bath before bed and do some breathwork and apply our sleeping balm- and I am off to the land of dreams.

Savoir champions innovative ideas and solutions that inspire a restorative night’s rest. Alongside honouring handcraft and only the finest, natural materials, we’re committed to discovering the ingredients – and benefits of sleep, that deliver a lifetime of unhurried luxury and health.
Learn more about ByNACHT here.