Soon the clocks will change – and as every year debates about the For and Against as well as the consequences for the public will start. Numerous impacts occur because many processes in the human body are organized rhythmically, for example heartbeat and breathing as well as the change between being awake and sleeping. Deviations from these rhythms – for example short sleep phases, working at night, not enough daylight, light at the wrong time or changing the clock in March and October – can even worsen health.

In the project CIRCADIA (Circadian Rhythms and Technology – desynchronisation in everyday life) Fraunhofer Institute for Systems and Innovation Research ISI and FOM University have investigated, how technologies have changed everyday life and its structures since the Covid-19 pandemic and which developments are possible in future.

How can circadian rhythms be supported?

After the scientists had questioned nearly 2,000 people about their daily routines, for example when using screens, they recommend in their publication “On the way to a chronobiologically enlightened society” a significantly broader education on the topic of circadian rhythms – including research in daily life and not just in the sleep laboratory.

There are many possibilities to allow individual people with their different chronotypes as well as society as a whole to get better and more sleep – and with that a better balance, better performance and more well-being

Three measures which can be implemented in the short-term are:

• Abolishing “daylight saving time”: From a chronobiological point of view standard time all year round is best for central Europe so that people get enough sleep. Changing the time in March and October upsets people's sleeping phases and the circadian rhythms, particular in late chronotypes. Prof. Kerstin Cuhls of Fraunhofer ISI says: “The term changing the time is wrong: we do not change time, but the clocks – and then we adjust to our clocks. Even if it is only an hour: this hour has proved to be a disturbance factor for health, well-being and performance. Some people have adjusted after a week but not all are able to and suffer.”
• Teenagers should start school later: Whether people are early, middle or late chronotypes is innate, but exactly how their internal clocks tick changes several times during a life time. In their teenage years, people are on average later in their biology than at other times in their lives. That's why many of them have a biologically based performance slump when they start school at 8 a.m. – according to their internal clock most people are still in the middle of the night. However, performance improves over the course of the day. Many teenagers can therefore hardly be expected to concentrate on learning at 8 o’clock in the morning, and school grades are difficult to compare between the different chronotypes.
• Valuing daylight as well as sufficient and quality sleep: Getting enough sleep and getting more exercise outside – especially in the morning, for example through sports or school lessons outside – is a basic recommendation to support circadian rhythms and should be supported by campaigns. In addition, indoor spaces, such as workplaces, are often inadequately lit. Since, despite technical advances, daylight cannot be imitated, at least architectural solutions should ensure that more daylight enters buildings.

Balance between own chronotype and social demands

These measures would be the first steps towards a chronobiologically enlightened society. Fraunhofer ISI and the FOM University of Applied Sciences understand this to mean a society that consciously deals with circadian rhythms in everyday life: People know their chronotype and structure their everyday lives accordingly, employers and educational institutions offer working and learning times tailored to different types, and night work, which is generally harmful to health, only takes place in systemically relevant areas such as security and medicine.

In such a society, “plenty of daylight for all” is a central health issue: leisure activities take place mainly outside, most meeting spaces are also located there, and the use of daylight is strongly integrated in new buildings. The aim is to reduce the amount of time people spend indoors and in front of screens, as has increasingly been the case, especially since the beginning of the Covid-19 pandemic.

Prof. Kerstin Cuhls from Fraunhofer ISI emphasizes: “The scenarios developed in the research project show that, in addition to temporal conflicts between everyday life, work and school, external effects will also have to be taken into account in the future. For example, heat waves caused by climate change can affect sleep, disrupting the circadian rhythm and affecting health. The effects of the digitalized world on internal clocks – keyword constant availability – should also be minimized.”

Therefore the authors advocate more long-term thinking. Foresight methods such as scanning of long-term topics, scenarios and spaces to experiment help to further research the issue and its long-term consequences for everyday life in the future. With that it would be possible to explore challenges and tensions between technology development, social change and individual rhythms. The study also shows that increased information about circadian rhythms can even contribute to better togetherness and understanding of each other.