Light is crucial for a functioning circadian rhythm - The light makes the body understand that it is time to start working
That we humans need light to feel good is hardly news to anyone. But during the dark winter months, it is difficult to get enough daylight for it to be enough. To compensate for the loss of daylight that the winter months entail, you can use artificial light. To get the most out of that light, there are some things that are important to consider.
Light is crucial for a functioning circadian rhythm
If you only stay in the dark, or if you get too little daylight, it will result in you becoming more tired, that you will find it harder to concentrate and that you will feel more depressed than usual. This is also why some people feel worse during the winter. The body simply loses its ability to maintain the natural circadian rhythm. Since many of our organs and half of all the cells we have in the body work so that they are active during the day and rest at night, we must boost ourselves so that we maintain a circadian rhythm that feels natural. Arne Lowden, who is a light and sleep researcher at Stockholm University's stress research institute, explains that it is good if, for example, the kidneys and liver do not work fully during the night when the rest of the body is resting, but that their activity is concentrated during the day when you are also awake.
The synchronization of cells and organs takes place when the brain receives enough information. That information should consist of light. The light makes the body understand that it is time to start working, and the darkness in turn tells the body that it should enter a less active position. The brain receives its information about light via receptors in the eye. Those receptors are most receptive in the morning, so to get the body going, it is good to get daylight before it is ten o'clock.
Ensuring that the body receives light during the day will also make the body sleepy in the evening. Arne Lowden emphasizes this and also that the body will recover better if the brain understands that it is night. Lowden says it can be complicated to compensate for the lack of daylight with artificial light, but that is not an impossibility.
Daylight and light from lamps
In order to be able to replace daylight, you need to know a little more about how the light is structured. The light is measured in lux and it indicates how much light there is per square meter. Outdoors, the light can amount to 5,000 or 10,000 lux, while indoors it is significantly lower, often around 500 lux. In order to get enough extra light, you therefore need to stay even longer in the artificial light than in the natural light. This can result in other difficulties, such as headaches or eye pain because the lights indoors are so strong. Lowden advocates that we should have as many lights lit indoors as possible to make it brighter, but at the same time points out that it can cause eye problems or pain in the shoulders and shoulders.
Hillevi Hemphälä is a researcher in synergonomy and connected to Lund University. Her studies are based on how to decorate with light to promote their well-being. Hemphälä believes that dazzling and flickering light sources indoors are not something our eyes are made for and that it is therefore always best to be outdoors to get enough light.
In order for lighting at home to be good, it must both light up directly and indirectly. If, for example, you only have one LED luminaire placed in the ceiling, the light will only be directed downwards and this can cause other parts of the space to be perceived as dark. The differences in light scattering can cause headaches and eye pain. To get a good spread of light, you must be careful in the choice of luminaire. Hemphälä recommends that the elderly have lampshades in metal to be able to direct the light where they want it, while fabric shades can instead be used to spread the light more. A tip she gives is that you can keep your hands in front of your eyes like the screen of a cap and control what feels best, to have your hands there or not to have it.
Hillevi Hemphälä is also careful to highlight that the flicker from LED lights is often not something we notice when we stay in a lit room, but that the brain still needs to filter out the flicker and that it can give a headache. This was a much bigger problem a couple of years ago and as the LED lamp has developed for the better, the problem has also become smaller even though there are still LED lamps that flicker.
Both Hemphälä and Lowden agree that the most important thing is to get enough light in the morning, but also to reduce the light in the evening. Hemphälä also says that you should avoid cold light in the evening by, for example, changing the light on your mobile to night shift mode around two hours before it is time to go to bed. In this way, you give yourself the very best conditions for a good night's sleep.