We all know how important it is to protect our eyes from the sun's harmful UV rays; but what about the harmful effects of blue light rays?
Before the advent of artificial lighting, days were spent with the rising and setting of the sun, and evenings were spent in relative darkness. Now, in much of the world, evenings are spent with illumination from other sources, and we pretty much take them for granted.
In its natural form, your body uses blue light from the sun to regulate your natural sleep and wake cycles. This is known as your circadian rhythm. Blue light also helps boost alertness, heighten reaction times, elevate moods, and increase the feeling of well-being. Artificial sources of blue light include your electronic devices, digital screens, your TV, computer, tablet, and smart phones. Also, LED lighting and fluorescent lighting give off blue light.
While there are many benefits of blue light, as mentioned, helps boost your energy, regulates your natural sleep/wake cycles, there are some very real harmful effects.
Being exposed to blue light at night, can actually reduce the levels of melatonin in your system, thereby disrupting your circadian cycle, or sleep cycle.
Study after study has linked working the night shift and exposure to light at night to several types of cancer (breast, prostate), diabetes, heart disease, and obesity. It's not exactly clear why nighttime light exposure seems to be so bad for us.
While light of any kind can suppress the secretion of melatonin, blue light at night does so more powerfully. Researchers at Harvard University conducted an experiment comparing the effects of 6.5 hours of exposure to blue light vs. exposure to green light of comparable brightness. The blue light suppressed melatonin for about twice as long as the green light and shifted circadian rhythms by twice as much (3 hours vs. 1.5 hours).
When our sleep patterns are disrupted, our days are also disrupted. We wake more tired, less likely to eat properly, which leaves us in a depressed state of not wanting to be as active as normal. All of these situations can add up to an overall feeling of not being ‘with it'.
Turning off the lights in your home, not having a television or computer in your room, will all lead to a better, more healthful nights' rest. Having a medical alert system available is also another way to rest assured that your health is a priority to others as well.