A 2010 study confirmed that blue light in the evening, especially from cell phones and computer screens, mimics the wakefulness-inducing effects of sunlight, Our widespread use of blue-wavelength light is likely a major factor in both chronic and acute insomnia. Compare modernized societies like the United states, which suffer from insomnia rates as high as 44%, to existing hunter gatherer societies, which suffer from insomnia rates as low as 8%. Science suggests that this disparity is largely caused by nighttime use of electronics.
The solution to much insomnia and some mood disorders is to simply emulate the hunter-gather exposure to light. First thing in the morning, get outside in the sunlight or use a light therapy lamp that emulates sunlight. Bright light in the morning can shift your sleep schedule up to 90 minutes! Read our reviews of white light therapy lamps here. Once the sun has set for the day, try to limit your exposure to blue frequency lights like laptops and cell phone screens. Consider purchasing an amber lamp or amber book light and spend the last half hour of the night reading quietly. Amber light in the evening has been proven to shift sleep schedules an average of 1 hour earlier! If an amber lamp isn’t feasible, studies show that amber night shift glasses, which block sleep-disrupting blue wavelengths, are also effective at preventing insomnia.
Our regulation of the sleep hormone melatonin and the mood neurotransmitter serotonin are largely regulated by our exposure to light. Studies demonstrate that careful regulation of light—getting plenty of bright blue-wavelength light early morning and afternoon and limiting your nighttime light to red-frequency light—may also help alleviate some forms of depression, particularly those like Seasonal Affective Disorders or SAD that result directly from seasonal light variation.
In short, pay more attention to your early morning and late evening light exposure to sleep better and be happier!