Although researchers don’t have firm numbers, many people are light deprived. Symptoms of light deprivation include:
The outdoor day–night cycle is essential to maintaining normal, healthy physiology. The importance of light - beyond vision - has been known in all cultures for a very long time.The scientific research effort however, is recent. It was inspired by findings that light exposure directly affects hormone levels and can reset the body's clock either forward or backward. Expert professional consensus recommends using diffuse white light that blocks out ultraviolet radiation (in contrast to the "sun lamps" used for tanning, which are dangerous both to skin and eyes).
Scientists think that light therapy works at several different levels, producing a combined beneficial effect. It is directly energizing for most people, thus combating mood-associated fatigue. In a natural environment when you wake up on the morning you would be exposed to the brightness of natural sunshine. The powerful brightness from the sun would turn off your melatonin production (sleep neurotransmitter) and stimulate the production of serotonin, the alert and feel-good neurotransmitter. When not exposed to light early in the day the continuation of melatonin secretion could upset your body's natural rhythm and sleep pattern.
Sunlight exposure first thing in the morning is the most effective form of light therapy. Sit with the sun shining on your face or take a walk toward the sun. The sun will indirectly penetrate the iris and affect the brain. You should not look into the sun, but the sun has to hit your face without sunglasses. During fall and winter, when it is not bright outside or too cold to be outside in comfort, a therapeutic light can be an effective substitute. When used at an appropriate morning hour (or in rare cases, evening hour) therapeutic lights:
Treatment regimens should be individualized and always with doctor's supervision in cases of full-blown clinical depression. Light therapy involves daily, scheduled exposure to intense levels of natural or artificial light in order to regulate seasonal mood swings, improve sleeping patterns, and produce a general sense of well-being.
Recent studies have indicated light therapy is also effective for non-seasonal depression, and I recommend combining light therapy with a high-nutrient diet and omega-3 fatty acids (DHA and EPA) supplementation. Learn more in my position paper Treating Depression Naturally.
I have researched the therapeutic lights on the market, and I recommend this Therapeutic Light which contains the features that medical literature reveals are critical to the effectiveness of light therapy for Major Depressive Disorder, Dysthymia, Bipolar Depression, Seasonal Depressive Disorder, PMS, Insomnia, ADHD, ADD, and Bulimia Nervosa. Studies show that light therapy may also be helpful in Fibromyalgia and Postpartum Depression as well.