10/11/2016
This week I was going to write about the Myopia Epidemic and Myopia Control but after last night’s on the I guess Blue Light may be a more pertinent topic.
So Watchdog went undercover in and Express and set about rubbishing claims about Blue Light Protection. It is probably fair to suggest that neither company did themselves any favours based on what was said by their employees. It was selling by fear. There was misinformation, lies and scaremongering. It showed a lack of understanding on the part of the employees and possibly a pressure to sell the product to hit a target to maximise profit.
That is clearly unethical, the role of a Dispensing Optician is to advise the patient based on need, whether that is prescription, work requirements, hobbies, or lifestyle factors. That brings me on to the fact that the staff pictured at Boots, except for one person, appeared to be Customer Advisors, not Dispensing Opticians. One person appeared to be wearing the DO uniform and we are not aware if they are qualified or not, however if they are qualified they need some intense retraining.
Watchdog however are guilty of unfairly portraying Dispensing Opticians as unethical snake oil merchants by repeatedly using the label DO when showing someone who appeared to be an unqualified advisor. The BBC should make clear the qualifications of the people pictured and if they are not DO’s they should apologise and make clear the level of knowledge and understanding required to be a dispensing optician and should a patient want to ensure they are getting the best advice based on their need and not a company profit margin then they should request to see a Qualified Dispensing Optician.
But what about the facts of what was said?
Watchdog claimed that there was no evidence for harm from Blue Light emitted by LED/LCD bulbs or screens and that there was no evidence that Blue Light filtering lenses provided any benefit.
A study in 2004 (found at this link) http://www.sciencedirect.com/science/article/pii/S1350946204000412
By T.H Margraina, , , M Boultona, J Marshallb, D.H Slineyc
“ Studies of human macular pigment density and the risk of AMD progression following cataract surgery lend further weight to the hypothesis that blue light exposure has a role in the pathogenesis of AMD but the epidemiological evidence is equivocal. On balance the evidences suggests but does not yet confirm that blue light is a risk factor for AMD. Given the socio-economic impact of this disease and urgent need to identify modifiable risk factors, future work should include a large-scale clinical trial to evaluate the effect of blue blocking filters on AMD progression rates.”
So more work needs to be done but we cannot discount Blue Light as a potential risk factor.
Up until the late 20th century the only Blue Light Exposure that humans had was from the sun. We woke to it, worked through it and slept when it set. AMD was not really known until more recently and its increase in prevalence has coincided with an increased longevity and the introduction of artificial blue light sources. That may be causation or it may be coincidence, we simply do not know.
What we do know, though is that the body appears to have a natural defence against a blue light damage. At the central fovea the body produces a yellow pigment called Meso Zeaxanthin. Meso Zeaxanthin is synthesised by the body from Lutein and Zeaxanthin and is only found in the one unique place in the body, at the fovea. So what does it do?
“ There is a growing and evidence-based consensus that MP is important for optimal visual performance, because of its blue light-filtering properties and consequential attenuation of chromatic aberration, veiling luminance, and blue haze. It has also been hypothesised that MP may protect against age-related macular degeneration because of the same optical properties and also because of the antioxidant capacity of the three macular carotenoids. “
J M Nolan1, K Meagher1, S Kashani1 and S Beatty1 2013
Meso Zeaxanthin appears to be the bodie’s natural defence against blue light damage and also works as an anti-oxidant to remove free radicals and protect against AMD. On its own it may well have been enough to protect against retinal cell damage when the only source of harmful blue light was from the sun. But today we have blue light emitted from smartphones, laptop screens, TV’s, energy saving light bulbs, xenon discharge bulbs. Our exposure to blue light is greater than our ancestors and combined with increased lifespans could well be attributable to increasing levels of AMD. Meso Zeaxanthin is destroyed daily and replaced by our bodies. In order to do this we need to ensure we obtain sufficient levels of the beta carotenoids to synthesise Meso Zeaxanthin. Unfortunately modern western diets are not great for this hence we also suggest supplements such as Thea Nutrof or Macushield (and others) to help replenish our beta carotenoids.
In a modern world with poor diets, increased screen time, and longer lives should we not be offering every option to help protect our patients sight?
Blue light filters may not be proved to work to prevent retinal cell death but it cannot be doing harm. In conjunction with other measures it may help to reduce incidences or AMD. The important thing is to be clear with our patients. Just yesterday I had a patient who was interested in Blue Light Filter Lenses for work as she was a VDU user. However after discussion I explained that I doubted they would be of use as she would only be using with the VDU. Had she been wearing them all day then she would have had reduced levels of blue light exposure from all sources and she may therefore have benefited from the potential protection offered.
The jury will be out on Blue Light filters for a while after last night’s programme but personally I see no harm and a potential benefit as long as it’s discussed appropriately.
Age-related macular degeneration (AMD) is a major health problem in the developed world accounting for approximately half of all blind registrations. Current treatment options are unsuitable for the majority of patients and therefore the identification of modifiable risk factors that may inform dise...