Light makes us happy or sad, it can soothe stress or. It controls the mind and stimulates physical healing processes. The lack of light in winter leads to blow people tribulation, be melancholic, at odds with himself and the world. Actually our body is still built for the outdoor life. And, actually, for hibernation.
Light therapy for seasonal affective disorder
In the early days almost all cultures worshiped the sun and its light. Assyrians and Egyptians already put 1400 BC to sunbathe for the care of their health. The Greek physician Hippocrates recommended the 5th Century BC solar radiation for the treatment of many diseases. And later the Romans sent their patients to cure stays happy to places with high solar radiation. But the knowledge of the therapeutic value of sunlight fell into oblivion during the Middle Ages. Only in the 19th Century, the curative effect was discovered. Medical importance of light therapy was then the 19th Century due to the success in the treatment of tuberculosis, and especially at the then widespread cutaneous tuberculosis.
And it was only about thirty years ago, physicians have begun, since 1993, the light therapy is recommended officially for treatment of winter depression.
One in four suffers
Winter depression is the remnant of hibernation in humans. Because it's in the winter - in the northern latitudes - cold for one thing and there is nothing to eat, need to save energy and for many animals fall into a kind of sleep mode, hibernation. And the same mechanisms, both at a corporate level and on hormone levels, take place in humans.
Here is changed by the extension of the darkness and the shortening of the day, the hormone balance and the man noticed the fact that in winter he has firstly an increased need for sleep and a craving for carbohydrates. And secondly occur lethargy and social withdrawal, typical symptoms of depression, in this case of winter depression. Included in the statistics, is that it affects more women than men, and that young women in particular suffer particularly common among them. The biological reasons for this, but for the research is still in the dark.
Challenge with light
Who has not had a chance to appeal for a morning walk and jogging, can fight his depression with a strong light lamp.
But it should emit at least 2000 lux brightness. This is the limit at which the light can reach its physiological effect.Lux is the illumination. It serves as a measure of the brightness, which arrives at the receiver. 2000 lux, for example, brings a cloudy winter sky. A cloudy sky in summer is already at 10,000 lux and a beaming Sommersonnentag makes even 100,000 lux.
Eternal day or night?
In most living rooms and offices our eyes can not get enough illumination to ask our inner clock to day. Usually there just 100 rule up to 500 lux produced by incandescent, halogen or energy-saving lamps. This means missing when we rarely go outside and move barely under natural light, then the body of the perception that it's day - it stays in sleep mode overnight.
Only when sufficient daylight or artificial light from the blue spectrum to the receptors in our eyes meet, then the production of the sleep hormone melatonin is inhibited. In addition, an increase in the "happiness hormone" serotonin is stimulated. Serotonin acts demonstrably positive effect on our mood. Therefore, the improved mood usually by enough light in the morning.
The sky in the Attic
Chronobiologists assume that the results of the research will be light in the coming years to a profound change in our lighting systems. A development of the lighting engineers at Stuttgart-based Fraunhofer Institute for Industrial Engineering IAO is the so-called "virtual sky" - the artificial sky. The entire ceiling of the show-room is covered with 50 x 50 cm large translucent bright tiles. At one point in the corner missing a plate, so you among the nearly 300 hidden LED lights in blue, can see red, green and white. They can be controlled by different computers.
For example, a sunrise in red and yellow to simulate. The most sought-after lighting situation, however, the dynamic light, which every now and then simulated and at different points of the ceiling passing clouds.
Living with Light
But not only working conditions, living conditions also can be improved by the selective use of the right lighting. In Germany, 90% of people in nursing homes suffer from Alzheimer's disease. And basically they are received there, because the relatives get any sleep. That means they sleep during the day quite often, but this is much more unpleasant as they migrate through the area at night. Here it has been demonstrated that with adequate lighting during the day, the nocturnal confusion in these Alzheimer's patients go back. Even for schools and universities is recommended to optimize the illumination.
Light is electromagnetic radiation. The visible to humans as light radiation extends over a wavelength of about 380 nanometers to about 780 nanometers. In the field of high-energy, short wavelength light is violet-blue, in the upper, less energetic red area. All other visible colors in between. Until the early 20th Century the sunlight spectrum has been measured accurately.
Light can initiate healing processes
In recent times, especially the blue light spectrum is investigated. At the skin clinic in Mainz has been studied as a therapy with high-energy blue light helps people with eczema. After all, ten to 15 percent of the population in industrialized countries suffer from it. It is an incurable disease that begins in varying degrees often within the first few years. The therapy used blue light has no anti-inflammatory effect, as one would expect from UVA or UVB light does, but it is believed that it acts at the level of immune modulation.
That is, it takes place counter-regulation of inflammation. In this way, the treatment with a self-healing is promoted, which is already created in the body, but bad for eczema or does not work. To extensive patient studies demonstrate the efficacy of treatment beyond doubt, however, still refuse the insurance companies to pay for the irradiation with blue light.
The blue light still seems to be the new leader in light therapy applications. At a wavelength of 435 nanometers aired on the skin, it will also be useful in the treatment of pain. It promotes the far position of the vessels, and the improved blood circulation, it can lead to a removal of such toxic substances, which are involved in pain mediation. Another medical field effect for the high-energy blue light is the healing of wounds. Initial studies investigating the theory that blue light promotes the healing of chronic wounds.
Light refuel against the winter blues
The simplest light therapy remains but those with sunlight. Because the therapeutic effect of natural light is guaranteed in any case. So, from outside and your eyes!