Maybe a year ago, I installed a free app called FLUX on my computer, making that decision based on what little I knew about the role of light–especially light wavelength–on daily cycles of hormones and other essential biology related to day and night cycles. What the heck, it couldn’t hurt. It visibly changes the blue cast of my screen to a redder wavelength at local dusk.
And a year later, I realize losing the blues from my monitor at dusk was probably a more important choice than i realized: blue is the body’s wake-up call. Many of us get too little of it during days inside, and then sit in a flood of it, in front of our blue-emitting monitors, before bed time. This is especially an issue of concern for older eyes, because more and more research shows far less blue light penetrates older lenses.
Many of the complaints and ailments associated with aging, some particularly of recent increase like depression and insomnia in the elderly, very likely are related to the changes in balance between the slow-down hormone melatonin and the go-gettem hormone, cortisol. And the eye is the gatekeeper for these changes.
“In a study published in The British Journal of Ophthalmology, Dr. Mainster and Dr. Turner estimated that by age 45, the photoreceptors of the average adult receiveÂ just 50 percent of the light needed to fully stimulate the circadian system. By age 55, it dips to 37 percent, and by age 75, to a mere 17 percent.”
“…the same amount of light that makes a young person sit up in the morning, feel awake, have betterÂ memoryÂ retention and be in a better mood has no effect on older people.”
So enough light and enough of the right kind of light during the daytime may make a difference, so be sure your golden years are blue. Take your shirts off, all ya, an go sit in the sun and read a book and sip a glass of wine (heck, take the whole bottle–red,Â preferably, with those anti-oxidants that lower the guilt) and tell’em Fred said it was alright.
- Older people more satisfied with sleep levels, study says (vancouversun.com)
- Ageing in eyes ‘linked to insomnia’ (time4sleep.co.uk)
- Aging Eyes Blamed For Seniors’ Health Woes (science.slashdot.org)