Sleep hygiene in winter: Why is it especially important right now?

Figure 1: Finding it difficult to fall and stay asleep in winter is a common phenomenon. Good sleep hygiene can support restorative sleep during the cold season.

As the days become shorter and darker, many people struggle with sleep problems. This can have a long-term negative impact on wellbeing and energy levels. The immune system also suffers from lack of sleep, which can make colds more likely during the cold season. In this blog post you will learn how and why our sleep changes in winter, and why good sleep hygiene is particularly important right now. With our tips for better sleep during the cold months you can stay healthy and energetic even in winter.

How does the sleep–wake rhythm change in winter?

Figure 2: Our internal clock – the circadian rhythm – needs to adjust to the new conditions of wintertime. On average people sleep longer in winter than during the summer months.

Perhaps you know this yourself: when the alarm goes off in the morning in winter, it often feels as if it is still the middle of the night. We often have to force ourselves to get up, even though we would prefer to keep sleeping. This increased need for sleep in winter is, however, perfectly normal. This is also emphasised by a study involving 300 participants with sleep disorders.¹ It showed that participants slept a full hour longer in winter than in the summer months. REM sleep phases increased by an average of 30 minutes. Although the researchers stress that the results are not fully representative due to the participants’ pre-existing conditions, it is likely that the observed tendency also applies to the general population.

That we feel more tired and need more sleep in winter is mainly due to our biological clock. This is also called the “circadian rhythm” and is primarily regulated by daylight. Because mornings are darker and evenings become dark earlier in winter, our sleep–wake rhythm shifts. The sleep hormone melatonin is released more during the day due to the lack of daylight, which explains the frequent tiredness and lethargy in the cold season.

What does “sleep hygiene” mean?

If you have never heard the term before, you are probably wondering what exactly is meant by “sleep hygiene”. In short, it covers all behaviours and conditions that promote restorative sleep. These include regular bedtimes as well as a suitable sleep environment and avoiding stimulating and potentially sleep-disrupting substances such as caffeine. What optimal sleep hygiene looks like is not only individual, but also varies with the seasons. Winter creates different conditions through cold and reduced daylight than summer with its long days and “tropical nights”. Later in this article you will learn why it is worth paying attention to good sleep hygiene especially in winter, and which practical measures can improve sleep.

5 reasons why good sleep hygiene is essential in winter

Figure 3: Lack of light, cold and an increased risk of infection are just some of the factors that influence our sleep in winter and thus the requirements for sleep hygiene.

The switch to winter time, which in Germany takes place each year on the last Sunday in October, forces the body to adjust to a new sleep–wake rhythm. During this transition period and throughout the entire winter the organism must adapt to specific conditions that can also affect sleep. Below we present the most important factors and their respective effects on sleep behaviour and quality.

1. The internal clock gets out of sync more easily

If you often feel tired and listless even during the day in winter, you are not alone. The reason for the leaden tiredness is a changed sleep–wake rhythm due to short days and lack of daylight.² Normally our “internal clock” – the aforementioned circadian rhythm – controls when we become tired. Light is the most important time-giver. In daylight our body produces the hormone serotonin, which makes us active. At dusk serotonin is converted to the sleep hormone melatonin. Because bright morning light is missing in winter, we often find it hard to get out of bed in the morning. The long period of darkness also leads to increased melatonin production. The result: you become tired earlier and remain groggy for longer in the morning.

2. The immune system is under greater strain

That we need strong defences especially in the cold season is well known. Often underestimated, however, is how much sleep also affects our immune system. While we sleep, the body reactivates and regulates many immunological processes. The production of immune cells and antibodies as well as inflammation regulation are supported by sufficient and regular sleep. Conversely, poor sleep weakens the immune system. As soon as sleep duration and quality decline, our defence cells respond less efficiently. It is therefore unsurprising that people who sleep less than six hours per night are, according to studies, significantly more susceptible to colds.³ Chronic sleep deprivation also raises relevant inflammation markers and often leads to existing infections lasting longer and being more severe.

3. Cold and dry heating air strain the body

In cold temperatures or even below freezing we understandably try to warm up. Turning the heating up full blast in all indoor spaces to make it cosy, however, is not a good solution. Dry heating air can irritate and dry out mucous membranes and airways. This in turn can lead to snoring and more frequent waking at night. Core body temperature naturally drops during sleep.⁴ Too high temperatures in the bedroom, however, often cause sweating or restless sleep at night. A bedroom that is too cold, on the other hand, activates stress hormones that negatively affect sleep. The body must continually expend energy to stay warm enough during sleep, which can disrupt nocturnal regeneration. Concrete tips and advice on the optimal bedroom temperature can be found in the next section of this article.

4. Lack of light affects mood

Weaker natural light in winter not only leads to increased melatonin release and consequently daytime tiredness. Lack of light is also associated with reduced serotonin production. As a neurotransmitter, serotonin is responsible for boosting our drive and regulating the circadian rhythm. It also stabilises our mood and promotes emotional balance – which is why it is often called the “feel-good hormone”. A measurable drop in serotonin in the winter months often results in a so-called “winter blues”. Many people suffer from low mood, lack of motivation and increased irritability. Vitamin D levels also have a significant influence. Because vitamin D is produced in the skin by the sun’s UVB radiation, many people in central Europe are under-supplied in winter. Vitamin D deficiency increases the risk of depressive symptoms, low energy and greater susceptibility to stress.⁵

5. Energy expenditure rises slightly in winter

The colder it gets, the more the body has to work to maintain core body temperature of about 37 °C. This happens, among other things, through shivering, activation of brown adipose tissue and a slight increase in basal metabolic rate. In the cold, daily calorie expenditure can rise by roughly 5 to 10 per cent.⁶ In addition, the immune system has to work harder in winter and therefore consumes additional energy. The higher energy demand in the cold season also means a higher need for recovery. Regeneration through sufficient and regular sleep is crucial to keep energy levels, mood, metabolism and the immune system stable.

Rested through the winter: Tips for better sleep in the cold season

Figure 4: Lifestyle plays a key role in sleep quality. Small changes in the areas of exercise, stress management and rituals can have a very positive impact on sleep quality in winter.

Suffering from sleep problems in winter is by no means unavoidable. Often small changes and sleep hygiene measures can help improve sleep quality. Below we present some tips that can help stabilise the sleep–wake rhythm and promote restorative sleep during the cold months.

• Get as much natural daylight as early as possible: Precisely because daylight is limited in winter, we should absorb as much natural light as possible. To support the circadian rhythm, it is sensible to go outside in the morning. Even a short walk in the fresh air can be highly effective and also helps combat daytime tiredness. If you cannot avoid spending most of the day indoors – for example due to illness or working from home – a daylight lamp can be a good support. Don’t darken your home unnecessarily and keep curtains and blinds open during the day to let in at least some indirect daylight.
• Keep a consistent sleep schedule: Our body loves routines. With a constant sleep schedule the organism learns when it is time to become tired and releases sleep hormones such as melatonin accordingly. Where possible, keep regular bedtimes and wake times even at the weekend to stabilise the rhythm.
• Establish a personal bedtime ritual: Rituals also help signal to the body that night-time rest is approaching. This could be a cup of herbal tea, reading, an audiobook or a warm bath before bed. Find something that does you good and helps you wind down in the evening. Essential oils such as lavender, bergamot or cedarwood, used in a diffuser or as a pillow spray, can also make it easier to fall asleep.
• Reduce stress regularly: Purposefully reducing stress should be a fixed part of your sleep hygiene not only in winter. As many studies show, stress leads to poorer sleep quality.⁷ Stress-reducing measures such as relaxation or mindfulness exercises, meditation or a gentle yoga session in the evening can noticeably improve sleep. To prevent ruminating and the well-known “mind-racing” from stealing your sleep, it can also be useful to write down on a piece of paper or in a notebook everything that is on your mind before going to bed. Tell yourself: “I can think about this again tomorrow, but now I will relax.”
• Stay physically active: Many people tend to move less in the cold season due to lack of light, cold or tiredness. Physical activity, however, offers numerous benefits that can also positively affect sleep in winter. Regular moderate exercise reduces stress hormones such as cortisol and promotes the release of relaxation-promoting neurotransmitters, making it easier to wind down in the evening.⁸ It is particularly beneficial to be active in the morning and during the first half of the day to stimulate circulation and natural hormone production. In the evening, avoid intense training sessions, as these can interfere with sleep.
• Don’t overheat your bedroom: Because hot, dry heating air can lead to restless sleep, avoid overheating the bedroom. A room temperature between 15 and 18 degrees Celsius is ideal for sleeping. If you are worried about feeling cold, you can warm the bed before going to sleep with hot water bottles, wear multiple layers of clothing, or use extra blankets. It is also advisable to humidify the room – for example with a humidifier or damp towels on the radiator. The idea that it is healthy to leave the window open at night is a myth. Cold air on winter nights can dry out the mucous membranes. In addition, the immune system is heavily taxed as it tries to protect the body from the cold.
• Minimise alcohol and caffeine: Even small amounts of alcohol can reduce sleep quality – especially REM sleep.⁹ You should therefore reduce evening alcohol consumption as much as possible or, ideally, avoid it altogether. Caffeine should also be consumed sparingly or avoided from midday onwards so as not to disturb sleep.

Disclaimer

This article does not replace treatment by a qualified therapist. The basis of this post is studies and current literature. It must not be used for self-diagnosis or self-treatment. If necessary, discuss ideas from this article with a therapist you trust.

Biography

Katharina Korbach regularly writes blog posts about medicinal plants and natural active ingredients for the Narayana Verlag. From an early age she became interested in language and began writing her own literary texts. A serious illness during her A-levels prompted an intensive engagement with health and nutrition topics that continues to this day. After the repeated failure of conventional medical treatments, she opted for a more empowering, naturopathic approach to therapy. A plant-based diet was an important factor in her recovery.

Katharina studied Cultural Studies (B.A.) and Applied Literary Studies (M.A.). In 2022 she published her debut novel “Sperling” with Berlin Verlag. She now lives in Berlin as a freelance author, medical editor and lecturer. She likes to spend her free time with friends or doing barre training. She also loves to travel and try out new vegan recipes.

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22.10.2026