• Blue Light

    Blue Light

    Blue Light in our visible Spectrum……..Something to Ponder?

    `Blue light’ and Ultraviolet light that is found in sunlight as well as artificial light affects us all, with respect to behaviour.
    It is the blue rays and UV that are given off by LED’s and fluorescent light sources in our environment, or given off from smart phones, tablet’s, I-pads, televisions, computer’s etc, the list goes on.

    I have recently returned from the International Congress for Behavioural Optometry. Both the research as well as the information is now available for all to read.
    Therefore as Behavioural and Developmental Optometrists: when we make suggestions about lenses, the lens designs or coatings, not only do we care for the general health of your eyes and visual system but also your overall general health.
    In order to explain what it is, what it does and how can we avoid the effects from this blue light I have to go back in time, sort of a history lesson:
    In the time when there was no television, cellular phones, computers and the like; we could listen to radio and read books, play games such as cards and the like. Have meaningful conversations. Life was far less stressful during that time. T
    Then the television, followed by the computer which eventually became a cellular phones which improved into smartphones, tablets, I-pads and the like. Now we even have I-pads for the tiny tots. Well these gadgets are all good and well, they keep us up to date with the very latest of whatever is happening around the world, and what about the human being!

    What is harmful Blue light?
    These blue rays of light and UV are present everywhere, both outdoors and indoors.

    Where can we find it?
    Fluorescent light sources and LED’s are incorporated in most modern devices.
    The rays being the Blue Violet light of which the harmful light range  is found in the 415-455 nm ranges (LED’s and digital screens).The Blue turquoise and visible light is essential range of 460-495 nm.
    The latest technological televisions, smart phones, computers, emit more than 40% more blue light than the ‘older generation’ pc’s. They all ‘look’ great and therefore we suspect they are wonderful, but, the blue spectrum on the display has been ‘tweaked’; adding a negative perspective to the detriment of the observer’s health and wellbeing. Should one compare an old cellular phone or television (which has far less blue spectrum compared to new technology) the older technology appears dull and uninviting.

    How does the ‘blue’ spectrum affect humans?
    An increase of ‘Melatonin’ (secreted in the brain), is a sleep molecule that controls your circadian rhythms. As the blue light fades at sunset, the melatonin increases and helps you to sleep naturally.
    But sunlight produces the blue light which activates the Melanopsin in certain cells of the retina to suppress the secretion of the Melatonin in the brain, therefore keeping you awake for the day.

    It has been found that Melatonin is suppressed by as much as 40%, and all thanks to modern technology: the increase in the ‘blue rays’ and the reduction in or no increase in melatonin has led to various issues, namely:
    Very poor sleep or little to no deep sleep causes one to get up, put the lights on and watch television again as sleep is not an option!

    How do the harmful blue light and UV influence the Visual System?
    As the levels of blue light increase so does the level of focussing increase, up to as much as 2 dioptres.
    Most people are working at a close range, whether it is computers, I-pads, cellular phones, kindle, Gobii etc. and reading under the LED and/or  fluorescent lights i.e. economy lighting. This leads to an increase in the visual system absorbing blue light which increases the focus levels, which leads to an increase in the stress hormones. This can go on ALL day. This affects the day-night cycle, wellbeing and could affect memory and general activity.
    Whereas: the increase in Blue Violet light from sources such as LED lights (remember the latest motor vehicle lights are also LED lighting), sunlight outside and digital screens. Too much of this is also associated with Age related Macular Degeneration.

    A little taste of what happens with respect to biology and physiology:
    You are driving down the road; it is dusk to night time, so the quality of the image on the retina is not very good. i.e. the picture that you are looking at, so your focussing increases trying to improve the picture on the retina when suddenly a new Audi is driving towards you. (Audi has the new Xenon headlights with LED’s…. There is huge impact of light on your eyes and due to the high density discharge of light from the LED’s, your pupil constricts (goes smaller) which affects the rods and cones in the retina due to the initial rapid pupil constriction together with the high density of light. This leads to a very slow recovery to a larger pupil size (because it is dark and the retina requires more light to ‘see’. It can take up to 30 minutes in some cases. This is detrimental to night driving.
    Therefore, the folk who have a job in which they drive predominantly at night. Have a behaviourally induced smaller pupil size (at night) e.g  4,5 mm instead of 5,5 mm. The field of vision for effective use of retinal rods (field) for night driving should be  a larger diameter pupil, as such, these drivers with a smaller diameter pupil size will lose out on their respective ‘night field of vision’, meaning they cannot use their visual system adequately at night. Would you be happy driving on the road’s at dusk or after dark?

    What about the effects harmful Blue light and UV light have on your wellbeing?

    Located in the centre of the brain, the Pineal gland secretes Melatonin, which is dictated to by light.
    Melatonin has two primary functions, the most important of which is to help control one’s circadian rhythms. As such: Light exposure STOPS the release of melatonin and in turn will therefore help to control the circadian rhythm. Melatonin secretion is low in daylight hours but high during dark periods, which therefore has influence over your reaction to photoperiod, which is the length of day versus the length of your night.

    Age related Macular Degeneration:
    Harmful blue light acts as a catalyst and therefore has a huge impact on this type of degeneration.
    Lipofascine accelerates cell death by A2E toxic metabolite which creates a by-product. A2E is photoxic.

    In my travels I have watched many children, playing with I=Pads, tablet or hand held games.
    On each occasion I noticed the children to be holding the `screen’ very close their face, and to add to the visual strain, there was no `break’ time from the activities. Noting of course: the `latest technology’ screen to be bright and excitingly clear. All of which will result in poor sleep patterns and poor behaviour patterns. Could this be what teachers and care givers are noticing during the day?

    So would you want a spectacle lens that is ‘off the shelf’ OR would you also start to think deeper now. I have the ‘Blue Control’ added to my lenses and what a difference it has made.

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