Hibernation – how the dark season affects our sleep
We are all familiar with spring fatigue, but very few of us are aware that winter also has a considerable influence on our sleep behaviour and our nightly regeneration. In fact, so-called winter fatigue means that our bodies are less able to recover despite relatively more sleep. But what exactly is the reason for this?
Increased need for sleep – 30 minutes longer in winter
The typical winter scenario is as follows: During the day we are constantly tired and at night we feel like we are always awake. According to a study by the Charité hospital in Berlin, Germans sleep on average half an hour longer in winter than in the rest of the year. Unfortunately, however, this extra half hour of sleep does not automatically lead to more rest.
The opposite is the case: many people do not wake up properly during the day and yet are not tired in the evening. The explanation for this lies in the winter circadian rhythm with short days, long nights and a lack of daylight. When it gets dark outside earlier, many people go to bed earlier, even though they may not be tired enough.
Most people have a natural 24-hour rhythm, also known as an internal clock, which is disturbed and shifted by the shorter periods of daylight and longer periods of darkness. Following our natural rhythm in winter would be the most relaxing solution, but as a rule, fixed working hours and a daily routine full of appointments prevent us from living according to our inner clock. Artificial light sources do the rest to enable us to live against our inner clock.
Melatonin – cause and effect of less sunlight
The hormone melatonin has a significant influence on our sleep behaviour. The sleep hormone controls our body’s own wake and sleep rhythm. Twilight and darkness promote melatonin production in our brain, while light inhibits its synthesis.
In winter, the dark season with frequent twilight and long nights, the body also releases more melatonin during the day. This is why in winter we often only really wake up in the morning after the sun has risen properly, and become tired again in the afternoon when the daylight fades again.
This vicious circle is the cause of winter fatigue, as you don’t really wake up during the day and yet are not really sleepy at night. The result: you don’t get enough rest during sleep. You feel tired during the day, lack concentration and are less productive. Tension, inner restlessness and nervousness can also be the result. Under certain circumstances, everyday demands become more and more of a burden.
Winter – darkness promotes tiredness and winter depression
Everyone has certainly experienced that a dark and grey winter can be hard on the mind. It’s dark when you leave the house and also when you come home. The short days and the grey, gloomy weather not only make you feel tired, but depressive moods are also more common in winter. You feel listless and lacking in energy, are particularly tired and often have an increased craving for sweets.
The increased melatonin production in the cold and dark season not only causes severe tiredness during the day. When melatonin is synthesised in the body, the happiness hormone serotonin is broken down. Serotonin levels fall, which can lead to winter depression or the so-called winter blues.
But we have good news: everything gets better in spring. With the days getting longer and the accompanying increase in daylight and hours of sunshine, winter depression and permanent fatigue usually come to an end.
