I watched a program with Katie Couric last night that I had recorded from part of The American Experience series. It was about the influence of technology on our lives now and in the future. Fascinating program if you can find it – it aired a couple of weeks ago.
One point that she did not touch on was the affect that light – all forms of light, both natural and artificial – has on our circadian rhythm (our body’s internal clock). I’d like to share a little info on that today.
When Light Hits Our Eyes
When the photosensitive cells in our eyes detect light, they send this information to the suprachiasmatic nucleus (SCN) – a group of nerves in the brain that controls our circadian rhythm. When the SCN detects light, it triggers alertness and delays the production of melatonin, a hormone that helps us to fall sleep.
Maybe that is why we just automatically want to dim our lights in the evening when sitting around relaxing, compared to the bright lights we blare during the day when in the kitchen or at our desks.
It turns out that the cells in our eyes are particularly sensitive to blue light, the shortest and highest frequency of the light waves detectable by the human eye with a wavelength of around 480 nanometers. Studies have indicated that longtime exposure to blue light can cause serious harm to our eyes, such as retinal damage and macular degeneration, greater risk of certain types of cancers, diabetes, heart disease, depression and obesity. And guess what! That is exactly the light wave our smart phones, tablets and computers emit! (Blue light sources also include the sun, fluorescent lights and LED lights.)
Exposure to blue light in the hours before bed has been proven to suppress melatonin levels, making it very difficult to get to sleep.
Never fear! The device manufacturers have found a way to keep us glued to our screens and still get some sleep. Here’s what to do:
Go to the Settings on your smart phone or tablet and look under Display and Brightness. You will see options to filter out the blue light. You can schedule a Night Shift/Blue Light Reduction between certain hours so as to automatically filter out the blue light. Slide the bar that appears for Color Temperature more to the warmer side.
Here’s An Idea
Better still – turn off those devices a couple of hours before sleep! Just read a physical book by lamplight, or mediate, or do some gentle yoga, or give yourself a moisturizing, relaxing reflexology session; anything other than staring at a screen. Give some extra love and attention to the reflexes of the eyes, pituitary and pineal glands, brain and diaphragm muscle.
And, if your eyes are sore from too much time in front of the screen during the day, or time spent outside in the direct sun without protection, lay down on your back with cool herbal-infused eye pads** covering cleaned eyes, while working the eye reflexes on your hands. They are found on the palmer side of both hands in the second and third digits in the most proximal of the three phalanxes. Simple, relaxing way if your eyes feel tired or sore – and a nice way to wind down before bed, too.
** Visit this link and scroll down to the description of Pharmagel Eye Pads. These are the ones that I use personally and with clients in our student clinics.