By Andréa de Paiva
For how many hours of the day are you exposed to natural light? For how long can you be outdoors feeling the sunlight hitting your skin? Or at what time of the day does the sunlight reach the windows of your home or office? If you can spend a lot of time exposed to sunlight, know that cases like this are increasingly an exception these days. The combination of indoor routines with the design of buildings and cities has made this simple and universal natural resource that is sunlight start missing from our lives. And science has been pointing out that this can bring great harm to our body, as we will see in this article.
Imagine that you have just bought an apartment. It is well lit, the windows and balcony are unobstructed with a great view and you go on with your life. Years later, buildings begin to appear in the surroundings and you lose most of the view from your windows. But this is not the only problem that you face. In addition to losing the unobstructed view, the sunlight that used to hit your apartment for a few hours of the day now only hits for a few minutes, exactly when the sunlight is most intense and, without protection, can be harmful. The leisure area on the ground floor, which had a garden and a pool with sunlight practically all day, is also not well lit anymore and, if you want to enjoy the pool in the sunlight, you have to go down at a specific time of day or else you will be in the shade.
Unfortunately, this is the reality for many people in different cities around the world. With the growing construction of taller buildings, as in São Paulo, for example, access to the sun, which was once a certainty in our lives, is now decreasing. And that doesn't just happen in our homes. This is a problem for other buildings like offices and schools, and it is also a problem in public areas like streets and parks. In New York, for example, there are discussions about the shadow of giant skyscrapers in neighboring buildings as well as in parks such as Central Park (Plitt, 2018).
But in the end, why does it matter?
Sunlight is essential for the maintenance of life on our planet. In addition to climate and seasons, the sun influences ocean currents and makes plant life possible through photosynthesis. But it's not just plants that need the sun to live.
The human organism regulates its internal activities according to the light and dark cycles of the day. This 24-hour cycle of the body's functioning is known as the circadian cycle, our "biological clock". We have cells in our retina that detect changes in lighting (natural and artificial light) even when our eyes are closed. In other words, it is mainly through lighting that our "biological clock" manages to synchronize the body's activities with the day and night cycles of the environment where we are.
In this sense, just as darkness is important at night for us to reach deep states of sleep, daylight is also important for our peak of energy. And although artificial light also affects - and a lot! - our "internal clock", during the day, natural lighting is unbeatable. For example, studies show that students in classrooms with more natural light have higher performance compared to students in artificially lit classrooms (Hechong et al, 2013; Baloch et al, 2020). In offices, workers with more access to windows have longer sleep duration (Boubekri, 2014) and positive effects on performance, in addition to decreased eyestrain and headaches (Hedge, 2018). The importance of natural light for our body does not stop there. In addition to regulating the biological clock, natural light is important for maintaining our health. Studies indicate that insufficient sun exposure may be responsible for about 340,000 deaths in the United States and 480,000 deaths in Europe per year (Chowdhury, 2014). In addition, correlations were also made between insufficient exposure to sunlight and increased incidence of some types of cancer, such as breast and colorectal cancer; hypertension, cardiovascular diseases, Alzheimer's, myopia, among others (Alfredsson et al, 2020). Sunlight is essential for the production of vitamin D and this, in turn, plays an important role in our health. It not only strengthens our immune system, but also helps to maintain healthy bones and muscles, regulate growth, control metabolism, among others (Wacker & Holick, 2013). In addition to the direct effects of insufficient exposure to natural light on our body, it is also important to highlight the effects that this generates for the quality of the environments. Sunlight is very important for the control of fungi and bacteria. In its absence, they proliferate more easily and the environment can become less salubrious. Have you ever heard of Sick Building Syndrome? This term is used when building occupants experience health and comfort issues, but no specific disease can be identified. One of the causes of the Sick Building Syndrome is the poor air quality resulting from both ventilation problems and the high proliferation of fungi and bacteria in humid environments with little sunlight. Last but not least, sunlight stimulates the production of serotonin, a substance associated with feelings of well-being and happiness, mood regulation and self-control, among other things. For example, a study in Australia found that people have higher levels of serotonin in the body on sunny days than on cloudy days which have less direct sunlight (Lambert et al., 2002). More than that, it is worth noting that low serotonin levels are associated with increased anxiety and higher risks of developing depression (Azmitia, 2010; Sansone & Sansone, 2013). That is, when we don't expose ourselves to sunlight, our levels of serotonin decrease, which not only affects our mood in the short-term, but can also lead to the development of depression in the long-term. In other words, spending a day in a poorly lit room may not be a problem, but if this condition becomes part of our daily lives, the effects on our body can be much more drastic.
What can we do with this knowledge? This knowledge is essential for us to understand more fully the importance of a balanced exposure to sunlight (no exaggerations, but no faults either) and, based on that, to rethink both our habits and our environments. We spend more than 90% of our time indoors (WELL Building Standard, 2014) and it is possible to say that this proportion has only increased with home office practices and with technologies that allow us to experience more and more moments of leisure without having to leave our home. Architects, designers and urban planners must to start from this point when designing new spaces. Starting from the inside out, we can bring more light to people while they are indoors. Since they spend so much time in these conditions, such solutions are even more important. How can we do this? Creating more (or larger) natural light entrances is a good start. But this is not enough! We need to lead people to the light. For this, the layout and uses of environments can be distributed in a way that areas closer to entrances of natural light become even more attractive. In addition, it is important to try to attract people to outdoor areas as well. Balconies, gardens, backyards, parks, squares and even sidewalks and bike paths create excellent opportunities for people to get more exposure to the sun. But just creating such spaces is not enough. Once again, we need to make these spaces attractive. We can achieve this by rethinking its safety, its comfort, its appearance, its functionality, its meaningfulness - among others - and by finding ways to increase people's emotional attachment to such places.
But, of course, there is no point in creating squares, parks, larger windows and balconies if there is no control over the buildings casting shadows on them. It is common that in discussions about the Master Plan for cities, the topic of the height of buildings is approached from the perspective of population density. We need to include the perspective of the shading of cities, the scarcity of natural light in public and private spaces, outdoors and indoors. Only in this way will this natural resource so important for our health and well-being not be stolen from us by the buildings around us.
The relationship between NeuroArchitecture and natural lighting is quite broad and is not limited to what we have discussed so far. Therefore, we will soon return to analyzing other issues related to the theme that can help architects and designers face this challenge!
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References:
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