HOW IMPORTANT IS LIGHT IN OUR LIVES?
Light is essential for our well-being and performance.
Each human cell synchronises its activity with the sun. The sun is the main food source for most life forms on Earth. However, it is not always possible to enjoy full daylight in a natural setting due to the demands of our modern lifestyles. We sometimes take for granted the challenge of living in northern latitudes. Modern lifestyles with shift work, long-distance travel, and indoor office lighting, coupled with changes of the seasons, affect the amount of light we get regularly exposed to.
Reduced daytime light causes a myriad of problems from winter blues, mood swings and general fatigue, to anxiety, sleep deprivation, carbohydrate cravings, and dulled spirits. These symptoms usually appear in the autumn and winter months when nights are getting longer and daylight is scarce. People who work in light-deprived environments or as shift workers during the night can also suffer from similar symptoms. The challenge introduced by northern latitudes and modern lifestyles is that ambient daylight is not often regularly available. Bright light therapy is a proven effective way to supplement natural light in your life.
WHAT IS LIGHT THERAPY?
Light therapy is a medical treatment that exposes the eyes to wavelengths of light of a specific intensity and visible spectrum very close to that of sunlight.
In most cases, treatment is recommended every day for a given length of time depending on the indication and prescription.
In some cases, light therapy is administered at a specific time of day. The salutary effect of light is linked to its physiological action, in particular, its influence on the secretion of melatonin, ordinarily known as the “sleep hormone” and serotonin, a neurotransmitter.
HOW DOES IT WORK?
Light stimulates photoreceptors present in the lower part of the retina thus activating the part of the brain that controls our biological clocks The biological clock sends the order to stop the secretion of melatonin
- Light stops the secretion of melatonin which serves to wake you up in the morning
- Light supplies energy
- Light assures alertness throughout the day
How intense is the light?
The light intensity of a light therapy lamp is defined in LUX.
LUX relates to the intensity of light received by the eye at a given distance from the lamp.
For a bright-light lamp, a thirty-minute treatment, 10,000 LUX (generally at a distance of 30 cm) is recommended.
For the blue-tinted lamp and a 30 minute treatment, 2000 LUX have been proven to have the same effectiveness.
LIGHT THERAPY TECHNIQUES
Light therapy is commonly administered using Light Boxes, Daylight Simulation Devices, Light Therapy Glasses and even through the ear using an Ear-light. Below we give a brief description on the various techniques:
There are a wide variety of light therapy boxes available in the marketplace today for home/work use. For the purpose of manipulating melatonin levels or timing, light boxes should provide very specific types of artificial illumination to the retina of the eye. For maximum effect the light box should emit up to 10,000 LUX of light at a specified distance, much brighter than your customary lamp. In treatment, the person’s eyes a prescribed distance from the light source with the light striking the retina. This does not require looking directly into the light.
LUMINETTE glasses were created as a result of the successful collaboration between three researchers at the University of Liege in Belgium. The researchers at the University of Liege got together to develop a light therapy device more ergonomic than existing systems, with a view to improve the patient/client comfort and therefore consistency of use. Their creation, Luminette, resulted from a collaboration between medicine and optics.