If you own a cell phone, iPad, computer or a laptop and have a hard time falling asleep, your technology might be to blame for your tossing and turning.
Within our eyes there are cells known as rods and cones, which are necessary for normal vision. Our eyes also contain retinal ganglion cells that store melanopsin. Melanopsin is particularly sensitive to blue light, a band of light in the narrow 400-480nm range. When blue light hits the retina a signal is sent to the hypothalamus and melatonin production is turned off and delayed by several hours. This results in an inability to fall asleep and causes difficulty when waking up, as melatonin levels are inappropriately elevated in the morning.
Blue light is everywhere and can be found within the displays of iPads, computers, laptops, cell phones. New government mandated CFL (compact florescent lighting) and LED (Light emitting diode) bulbs, which give out much more blue light than the previous versions, can also create an excess of blue light. With this increase in blue light exposure it’s no wonder we are seeing an epidemic of sleep deprivation.
A lack of sleep can manifest itself in many way such as; increased stress, cognitive dysfunction, chronic diseases mood disorders and obesity. In fact, in a recent study, hamsters exposed to blue light at night developed cellular changes in an area of the brain called the hippocampus. This part of the brain is very much involved in memory and emotional processing.
So, short of going back to pre-industrial revolution conditions, what can we do to decrease our exposure to blue light and get our circadian sleep wake cycle back to normal? You can turn off your laptop, iPad, and other electronics gadgets, including that your LED TV, at least two hours before bedtime. You can also use red night lights in your bedroom for illumination; since red light has the lowest effect on melatonin production of all light wavelengths.
Another idea, which I have instituted successfully, in many of my patients is to where blue blocker sunglasses at night. These are very effective in screening out blue light. Finally, there is available a computer program that alters the color of your computer display according to the time of day it is called F.Lux and can be found online.
The bottom line is that we are being bombarded with blue light. More than 200 million computers are purchased worldwide per year. We need to be aware of what I would call blue light pollution. By taking measures to prevent over exposure at the wrong time of day we can do much to improve our health.
