Everyone should have noticed for themselves what science has adequately proven in numerous studies since the 1970s: the light has a beneficial effect on the human organism. At least when it comes to natural daylight or sunlight. You feel more alert, fitter, more productive. In short, just happier. Especially in summer when there is enough natural sunlight. In winter, however, at work and in our own four walls, depending on the season, we are dependent on a lot of artificial light, which - depending on the dosage - can in the worst case even make you sick. The connection between light and health cannot be dismissed out of hand. But how and when does light influence our biorhythm?
The first rays of sunshine arouse spring fever, while many people first get autumn depression at the end of the year and then fall into the winter blues. In between, in summer, the days are particularly long and most people are accordingly active or productive. This is due to natural sunlight, which has been proven to have a beneficial effect on the human organism and its biorhythm.
The human biorhythm is determined by light
Humans are naturally used to the daily and seasonal changes in the sun and adjust their biological clock, the so-called Circadian rhythm, accordingly. Because - and researchers have proven this many years ago - there are light-sensitive cells everywhere in the body that react to natural daylight on the one hand, but also to artificial light. The complex receptor system of ganglion cells located on the retina in the eye plays a very special role in this regard. Because depending on the light color or color spectrum of the light that hits these ganglion cells, the human organism produces hormones that adjust the body to the corresponding phases and tasks in a 24-hour Circadian rhythm.
Sunlight has an activating effect in the morning and calming in the evening
Stimulated by natural daylight in the morning or noon, the body releases the activating hormones serotonin and cortisol, which are real stimulants. In the evening, when the sun goes down and the natural light becomes warmer or warm white, the body produces more melatonin, which is also known as the so-called "sleep hormone" and ensures peace. The reason for the different effects or effects is the different color spectra of the light and the associated change in color temperature, which can also be imitated depending on the luminaire or (LED) light source. If the blue component is higher, as in cold white or daylight, it has an activating effect. If, on the other hand, the red component predominates, as in evening sunlight or warm white light, it has a more calming effect on the human organism.
Artificial lighting: Less is almost always healthier
In the opinion of almost all light researchers and medical professionals, light plays a crucial role in people's health, wellbeing and performance. That is why light is often referred to as the “medicine for happiness”. Provided, of course, that it is optimally tailored to the respective situation and the specific requirements or tasks. Since natural sunlight is only available to a very limited extent, especially in winter, artificial lighting plays a major role. After all, people spend a large part of their lives indoors. A balanced mixture of daylight and artificial lighting has always been considered optimal for lighting rooms. The more natural light there is, the better. However, depending on the design or location of the workplace, there is unfortunately too little or no daylight in many rooms.
Artificial light has a different color spectrum than daylight
A lack of daylight can have negative effects on the human organism and, for example, cause so-called "light stress", as the light researcher Prof. Dr. Fritz Hollwich has already proven in the 1970s. Since artificial light differs considerably in its spectral composition from natural sunlight, it has a different, mostly activating effect on the human organism. And because artificial light suppresses the melatonin production in the human body, the natural sleep-wake rhythm is influenced by it. Too much artificial light messes up the internal clock if it does not change its light color or does not adapt to the natural course of daylight of the sun.
Too little daylight: researchers warn of negative long-term consequences
Numerous scientific studies have shown that long-term consequences of a shifted daily rhythm are, in addition to lack of sleep, above all depressive illnesses, a higher risk of tumors, and even heart attacks. To minimize these disease risks, scientists and doctors recommend extensive use of daylight and the use of artificial light luminaires that can change their color temperature in line with the natural course of sunlight during the day. Fortunately, in times of modern LED lighting, this is possible, especially in the workplace, only the appropriate lights have to be used. So-called biological lights such as the LED floor lamp from Sunmory are usually more expensive to buy, but they work real wonders. Ultimately, they increase people's ability to concentrate and perform, and thus also people's well-being. And after all, that should be important to every boss.
Conclusion: Researchers have already proven in the 1970s that light has a decisive influence on human health. Natural sunlight or daylight has a particularly positive effect on the human organism; too much artificial light, on the other hand, can disrupt the biorhythm and have negative consequences.