In social media workshops with parents and teachers a number of concerning issues normally surface: cyberbullying, porn, online privacy, sexting, inappropriate sharing, loneliness and issues around defamation. The recent case of a young Capetonian girl who was almost recruited by Islamic State online is also often a talking point. Seldom, however, are other health issues, like the effect of blue light from LED screens, mentioned. This can be just as damaging – in the long term. By RUSSELL POLLITT.
Earlier last week SABC chief operating officer Hlaudi Motsoeneng, called for the regulation of social media such as Twitter and Facebook. He was addressing government communicators at the University of the Witwatersrand School of Governance. “We must also regulate social media, it can’t be right (that) some people destroy other people’s lives,” Motsoeneng said. He said freedom of speech goes hand in hand with accountability and responsibility. There are, however, other reasons why we should be watching just how much we use social media.
Scientists in the US claim blue light emanating from screens is having a detrimental effect on our health. For a number of years scientists have been saying that being in the presence of blue light at night disrupts the body’s natural circadian rhythms because it suppresses the production of melatonin, a sleep hormone. However, melatonin is more than just a sleep hormone, it is also an antioxidant that could play a pivotal role in slowing the progression of cancer and other diseases.
The impact of blue light on melatonin production was only confirmed in 2001. Scientists found the blue light spectrum, 415-445 nanometer range, disrupts melatonin production.
Dr Richard Hansler, from John Carroll University in Ohio, has spent 20 years studying the effect of blue light on health. He claims he has learnt that the blue component in ordinary light is what suppresses the production of melatonin. Hansler says melatonin helps sleep but also plays a role in preventing diabetes, obesity, heart disease and a few types of cancer. Delayed melatonin production due to blue light exposure is causing many more problems than just insomnia. Optometrists, he says, are seeing higher levels of retinal stress in young people that could lead to the early onset of macular degeneration. In extreme cases this can cause blindness because it causes the loss of central vision – the ability to see what’s in front of you.
Blue light is widely used in all LED devices – phones, tablets, laptops and televisions. Blue light is part of the full light spectrum which means we are exposed to it via the sun everyday. However, night time exposure to this light – which is emitted at high levels by smartphones – has only been so heavily concentrated in our light sources for the past 10 or 20 years. (Previous incandescent bulbs don’t emit the same amount of blue light.) Smartphone screens emit high levels of blue light so that you can see them even at the sunniest time of the day.
Dr William Harrison, an optometrist in Laguna Beach, California, has been following the research on blue light closely. He claims it is compelling but says the medical profession is slow to catch onto the concerns that have been raised. “Here is what does not need research: 415 to 445 nanometers is super hot light, and if it’s really focused and brought up close – when you talking about a tablet six inches from a kids face – it’s got to be significant,” he says.
The more Hansler conducted his own research on the impact of blue light, the more he felt compelled to do something. In 2005 he and a group of physicists at John Carroll University developed lightbulbs that don’t emit blue light and goggles that block out that part of the spectrum. Hansler says there are screens that claim to filter out the blue light as well as applications that let you put your device in a bedtime mode where the light contains less blue and more amber. He is suspicious of whether these actually work and says more research needs to be done.
It is interesting to note that lens manufacturers are, for example, placing a coating on lenses. They claim the coating neutralises the blue light emitted from screens. This, they say, prevents eye fatigue, eye strain and even sleeplessness.
Blue light is not bad all the time. At times it is actually beneficial to health. Light tells us when to wake and when to sleep. Bright blue light sends a signal to the brain to stop producing melatonin; it also primes the brain to start producing the hormone again later – in theory when you are preparing to go to sleep. Some experts recommend that, in the morning, getting an hour of early sunlight without sunglasses is good. The light gets through the retina and signals to the pineal gland that controls melatonin production that it is day. At night, however, screen usage can convince our brains that it is morning and that they should, therefore, not produce melatonin. This can cause sleep disturbance and other potential problems.
The disruption of sleep has damaging side effects. It can leave you distracted and impair memory; it can also make learning harder. It can have an impact on thermoregulation, blood pressure and glucose homeostasis. Over a long period, insufficient sleep can lead to the build up of a neurotoxin that makes it even harder to get a good night's sleep.
Studies show that people whose melatonin levels are suppressed and whose body clocks are thrown off are more prone to depression. The higher incidence of depression globally could have, as a contributing factor, lack of sleep. Disrupted melatonin and sleep can also interfere with hormones that control hunger that, in turn, have the potential to increase obesity risk. Studies show that blue light is a 'carcinogenic pollution' and that, in mice, it correlates to higher cancer rates. A lack of melatonin is linked to higher rates of breast, ovarian and prostate cancers. Blocking blue light with amber glasses is linked to lower cancer rates.
Researchers are also investigating whether or not blue light leads to an increase in cataracts and if it could damage vision and harm the retina over time. Too much blue light, researchers think, could cause retina toxicity. It must be noted that most studies show the light needs to be held pretty close to the retina for this to happen. This may not replicate typical phone use – unless you are lying in bed with the phone close to your eyes.
While Motsoeneng’s idea of regulating Twitter or Facebook is probably going to be as successful as trying to regulate the taxi industry, religion or, for that matter, the amount of steps you take each day, it seems as if we would not be amiss to practise some self-regulation when it comes to the use of screens before bed. It also begs the question: Is the shift in education to more and more technology ultimately going to help future generations?DM
Photo: An Apple employee (2L) and a technology journalist (L) look at the new iPad Air during the launch at the Apple Store in central London, Britain, 22 October 2013. EPA/FACUNDO ARRIZABALAGA
Written by Kristen Fischer | Published on 2015/10/12
The time children spend on tablets, phones, and computers can seriously strain their eyes, but it’s also hard on their backs and necks.
It seems like children know how to operate tablets, smartphones, and computers almost from birth.
But those mesmerizing screens expose them to a number of long-term health threats.
The American Optometric Association’s (AOA) 2015 American Eye-Q® survey found that 41 percent of parents say their kids spend three or more hours per day on digital devices. It also found that 66 percent of kids have their own smartphone or tablet.
Too much screen time can result in digital eyestrain, which can include burning, itchy, or tired eyes. Headaches, fatigue, blurred or double vision, loss of focus, and head and neck pain are other threats for children using screens too often and too long.
“The short-term effect of digital eyestrain is not cumulative,” Dr. Tina McCarty, an optometrist from Minnesota and member of the AOA Public Policy Committee, told Healthline. “The eyes will get better when you give them a break and/or wear the proper eyewear in the form of lenses and coatings based on the patient’s specific needs to minimize eyestrain.”
Electronic devices also give off high-energy, short-wavelength blue and violet light.
This light can affect vision and cause premature aging of the eyes. Early research shows that overexposure to blue light can contribute to eyestrain and discomfort. It also can trigger serious conditions later in life such as age-related macular degeneration, which can lead to blindness.
“We know that damage from UV light is cumulative in the eye and that a lifetime of protection is critical in protecting from certain eye-related disease as we age,” said McCarty. “Blue light is very near UV light in wavelength and energy and therefore there is concern for cumulative damage over a lifetime of exposure.”
We know that damage from UV light is cumulative in the eye and that a lifetime of protection is critical in protecting from certain eye-related disease as we age.
Dr. Tina McCarty, American Optometric Association
The younger eye typically has a keen ability to accommodate and focus on close objects as the natural lens of the eye is smaller and clearer, she said. However, the accompanying blue light is more easily transmitted to the retina, potentially causing damage.
Blue light can also interrupt sleep patterns and circadian rhythms when children view screens close to bedtime.
Toddlers may still be settling into healthy sleep patterns, so McCarty says it’s even more critical for blue-light exposure to be eliminated long before these children go to bed.
She said there is “increasing evidence to support a link between blue light exposure and macular degeneration.” Long-term effects of blue light exposure are still being studied, though.
To protect their eyes and vision, children should take frequent visual breaks. Use the 20-20-20 rule: Take a 20-second break every 20 minutes and look at something 20 feet away.
As far as how many hours a day your child should be allowed to use a digital device, McCarty said there’s no standard for what’s safe. Taking breaks is the best way to protect their eyes.
Children should also have eye exams each year as their eyes are still developing between the ages of 5 and 13.
“Be sure that children have had an annual comprehensive eye exam to find out if the digital devices are causing any eye problems,” McCarty said.
If there’s a problem, it’s easier to correct when detected early. Vision and eye health can also affect a child’s learning capacity.
It’s not only the screen that can cause problems. The position a child assumes while using an electronic device is also important.
Dr. Peter Ottone, a chiropractor from New Jersey, said that poor posture from computer and tablet usage has become epidemic.
“This problem has always affected adults but increasingly is having an effect on children's spines and postures as well. With increasing computer usage for school as well as for leisure enjoyment, the time kids are spending on computers is ever increasing,” he told Healthline.
The slouched posture students often use when at a computer workstation increases pressure on the spinal muscles, ligaments, nerves, and disks. This increases the susceptibility for neck pain, back pain, and headaches, Ottone said.
“I have noticed a large increase in teen and preteen kids with these complaints enter my office over the past several years,” Ottone said.
I have noticed a large increase in teen and preteen kids with these complaints enter my office over the past several years.
Dr. Peter Ottone, chiropractor
He reports also seeing a lot of cases of “text neck” from extensive mobile phone usage.
For computers at desks, Ottone said that the top of a computer screen should be at or only slightly below eye level. The chair should allow the user to be as close to the mouse/keyboard as possible so as to eliminate reaching. The feet should be flat on the floor or placed upon a raised surface.
When a child uses a tablet, the same principles apply, but a pillow should go under the forearms to raise the tablet to the appropriate level so the child doesn't have to look down at the screen.
“This will also relieve some pressure from the wrists, eliminating possible carpal tunnel and tendinitis conditions,” Ottone said.
“Parents should take the time to make sure their kids are using proper ergonomics with all these devices and encourage kids to take regular breaks from these postures to help reduce the overuse syndrome risks,” he added.
There’s a lot of evidence that blue light, emitted by smartphones, tablets, laptops, and many other electronic devices, is impacting on the quantity and quality of the sleep we are getting. Darkness is a natural cue to our bodies that it’s time for sleep, but we’re circumventing it by staring at bright screens for hours after the sun has gone down.
You can decrease your exposure to blue light in a variety of ways, beyond turning off all the light sources. There are special filters, glasses, light bulbs, and even software you can use. But, before we get into that, let’s delve into the science behind it.
What’s the problem with blue light?
Blue light tells our brain that it isn’t time to sleep, according to the experts.
“There are about 30,000 cells inside your eye that are reactive to the wavelength of light which would be considered blue,” explains clinical psychologist and sleep therapist, Dr. Michael J. Breus. “Blue runs in about the 460 nanometer range, in terms of the spectrum of light. That particular spectrum of light hits these cells and makes them send a signal to an area of the brain known as the suprachiasmatic nucleus and tells it to turn off melatonin production. Melatonin is the key that starts the engine for sleep.”
The impact of blue light has been well-known to sleep researchers and scientists for many years now. Our circadian rhythms determine our internal clocks. Someone who routinely stays up late probably has a longer rhythm than an early riser. Daylight traditionally keeps those rhythms aligned with our environments. Blue light therapy is frequently used to shift sleep patterns and tackle sleep disorders.
“In the past 50 years, there has been a decline in average sleep duration and quality.”
The paper assessed two groups; half read a normal printed book for four hours before bedtime for five consecutive nights, while the other group read a light-emitting ebook reader for the same period. The patients using the ebook reader showed suppressed levels of melatonin. On average, they took 10 minutes longer to fall asleep and displayed significantly less rapid eye movement (REM) sleep than the group reading printed books.
Unsurprisingly, the ebook reader group reported feeling less tired in the evening, but they also reported that they felt more tired in the morning, despite having the same duration of sleep as the other group.
There are more serious health issues to consider if you aren’t getting enough sleep. When our circadian rhythms are thrown off researchers believe we are put at more risk of all sorts of things including heart attacks, obesity and type-2 diabetes, and various cancers. Those examples are mostly related to long term night shift, or severe sleep disorders, but any disruption to your circadian rhythm can cause problems. Lack of sleep has also been linked with mood problems, anxiety and depression, and increased risk of accidents.
Can blue light damage our eyes?
There are also some scientists linking blue light to age-related macular degeneration, though the evidence doesn’t seem to be conclusive. Over exposure could be playing a role in the rise of cataracts and even blindness.
“We are seeing a much greater number of age-related macular degeneration patients, even back correcting for the aging population, so the risk factors are clearly changing,” explains Professor John Marshall, Frost Professor of Ophthalmology at the Institute of Ophthalmology in London, “If you look at cataracts there’s a very good correlation between the age of onset of cataracts and the degree of ultraviolet where you live in the world, that’s why people close to the equator tend to get their cataracts 5 to 10 years earlier.”
We know ultraviolet (UV) is damaging and the blue range is closest to it. For damage to the eye, the peak wavelength for blue light is around 440nm, but the suppression of melatonin is higher, at around 460nm.
“By far and away the biggest exposure you’re going to get is from the sun – that is the biggest blue light hazard that you will meet in your lifetime,” says Professor Marshall. “The big red herring here is smartphones. If you actually do the calculations from the spectral emission of those things – it’s tiny.”
The risk of damage has a great deal to do with power and brightness.
“Light bulbs are much brighter sources,” explains Prof. Marshall. “When was the last time you got an after image from looking at your iPad? When you look at a light source, especially an LED, you’ve got that multicolored image on your retina which takes a long time to fade.”
“Until recently, we lit our homes with incandescent bulbs and they were relatively biologically friendly, in that there was very little blue,” says Prof. Marshall, “More commonly now they’re LEDs and these light sources have a lot of the potentially damaging blue, to the extent that I don’t use them.”
Turning everything off and sitting in a dark room is not something many of us will do.
There’s a Florida company called Lighting Science Group which offers a line of “biological” lighting. You might opt for a warm light bulb that emits lower levels of blue light for your bedroom, and use an Awake & Alert bulb in the kitchen to get you going in the morning along with your first cup of coffee. There is evidence that the bulbs we use can also impact on our circadian rhythms, and worse, affect our skin the way that the sun does, but this usually requires close, prolonged proximity.
A lot of bright lighting is obviously going to be an issue, that’s often a problem for night shift workers, depending on their environment. For most of us, subdued lighting towards bedtime is going to be enough to make a difference. But, what about the blue light coming from our devices?
If you’re really concerned about blue light exposure, then there are bigger fish to fry than smartphones and tablets.
“Wear a big hat, appropriate sun glasses, and consider the lighting in your home,” says Professor Marshall. “If it’s iPads and iPhones, I wouldn’t worry.”
The right balance of blue light
“There’s nothing wrong with blue light for most of the day,” says Dr. Breus. “You just don’t want to have it about 90 minutes or so before bed.”
Sunlight has a tremendous amount of blue light in it. The worrying negative effects are connected with the melatonin deficit and disruption of circadian rhythms that leads to less sleep and poorer quality sleep. But, we need blue light to get us going in the morning, and it has been linked with higher levels of alertness.
“When we wake up in the morning our circadian rhythm is a little off, our internal biological clock runs on a slightly longer schedule in many cases than 24 hours, and so to reset that clock every morning we need sunlight,” says Dr. Breus. “One of my biggest recommendations for patients is every morning go outside and get 15 minutes of sunlight.”
At the other end of the day we need to be more mindful of our blue light exposure. Proximity is an important factor. That’s why smartphones, tablets, and laptops are perceived as a bigger risk than light bulbs or TV screens. Though, it’s worth remembering that the impact on sleep is about more than just the blue light exposure.
“I think there’s a second factor that people aren’t really talking about that much, and that is the level of engagement in whatever the device is,” explains Dr. Breus. “If you’re playing your favorite game, or whatever it is you like to do before you go to bed, you’re mentally engaged in that act.”
Let’s be honest, turning everything off and sitting in a dark room is not something many of us will do. Thankfully, there are alternatives.
How to filter blue light with special glasses
There have been protective glasses on the market for a while, but they tend to have colored lenses. Now, we’re beginning to see alternatives that aren’t so strongly tinted, such as the Jins Screen range of glasses, which have been specifically developed to address the blue light problem.
“They reduce the transmission of light in the 460 nm range by 25 percent via two pathways: coating and substrate,” explained Lilian Wouters, PR Manager at Jins. “Certain wavelengths of blue light are reflected by the patented coating on the lenses, while others are absorbed by the substrate, which is made of a compound that absorbs certain wavelengths of blue light.”
You can pick them up as standalone non-prescription specs, but the special coating will also be available on prescription glasses.
There’s also a newcomer on the scene, called Gauss, which recently smashed its Kickstarter target.
“Gauss glasses come with lenses that have multiple layers of coating applied to them. Each layer has different properties and all this combined results in our Blueguard coating,” developer Jay Uhdinger told us. “It reflects light peaking with the wavelengths of 400 to 440 nanometers, while still letting other wavelengths pass through, to enable people to still see blue as blue with minimal impact on normal color vision. Studies show that these frequencies can cause most damage to the retinal pigment cells of the eyes.”
Blue light is just one of the factors that determines your sleeping pattern, but it’s clearly very important.
With self-tinting lenses and UV blocking, Gauss glasses are intended to serve as sunglasses and offer indoor protection. They are designed primarily to protect your eyes against the potentially harmful 440nm peak blue light, but they do also filter 460nm light that might impact on your melatonin production.
“Our goal was to create the perfect sunglasses for the digital age because it is simply easier for people to carry around one pair of glasses that they can use to protect their eyes while they are outside or when sitting in front of a computer or other digital device screen,” says Uhdinger.
The science behind these glasses appears to be sound. There is a lot of research on lenses that block blue light and they do seem to have a positive impact on sleep quality. Jins was also a sponsor of the recent New York Blue Light Symposium which had various academics presenting research on blue light and its negative impacts.
Why not use software?
One of the most popular options right now is F.lux. It tweaks the color of your computer’s display according to the time of day, so it gets warmer at night and has more blue throughout the day. It’s completely free and you can use it on Windows, Mac, Linux, and jailbroken iOS devices. There’s an app called Twilight on Android that does the same thing.
We asked Uhdinger why people would use glasses over software and here’s what he said,
“We think apps like F.lux or Twilight are great and everyone should use them. In fact, they should be part of future operating systems. Gauss glasses just add another layer of protection because unless you completely turn off the blue color channel in your monitor it still emits blue light. Plus many other sources of blue light like light bulbs with cold color temperatures still emit blue light that interferes with your melatonin production and as a result, with your circadian rhythm.”
What works to reduce blue light?
I’ve been using Twilight and F.lux for a couple of weeks and it does feel like it’s made a difference. Just like millions of other people, I tend to read on a screen in bed, with no other light source, and since using the apps I have felt tired earlier and fallen asleep more easily than before. Judging by the reviews and discussion online, a lot of people feel the same way.
I’ll be getting a hands-on look at the Gauss glasses very soon, so stay tuned for more on that.
In the meantime, think about your exposure, and if you’re having trouble sleeping, try modifying your lighting and device use. Blue light is just one of the factors that determines your sleeping pattern, but it’s clearly very important. Some experts recommend staying away from devices for a half hour before sleeping.
“Would I say we have a health problem because of phones and tablets shining light in our faces? I would say, yes we do,” Dr. Breus told us. “But, they’re not the only factor.”
A Palmerston North optometrist is warning that light emitted from smartphones, tablets and computers could be putting users at risk of early onset macular degeneration.
Harmful 'blue-violet' light is emitted from the LED screens of devices such as smartphones and tablets, and close proximity to the light makes the risk of damage worse, as well as contributing to eye fatigue, according to optometrist Brian Naylor, of Visique Naylor Palmer.
He said the blue light damage was of growing concern as people spent more time on digital devices while working and studying, and children were exposed at an early age to screens.
"Recent figures show that a typical multiscreen user in New Zealand is clocking up just under seven hours of screen time daily, which includes laptops, TV and smartphones," Naylor said.
"All of these emit significant amounts of blue-violet light, which is the highest-energy wavelength of visible light, and because of that can penetrate through the eyes' natural filters, all the way to the back of the eye."
The effects of blue light are believed to be cumulative, and computers are the worst culprits, closely followed by tablets and smartphones.
"Over-exposure to blue light can cause headaches, dry eyes, and difficulty sleeping in the short term, and there are potential longer-term effects that we are also worried about."
Naylor said, in particular, blue-violet light was a proven risk factor of age-related macular degeneration (AMD), along with genetic factors, smoking and diet.
He recommended that those who spent long periods of time on computers, tablets and smartphones, think about protection, including lenses specially designed to help filter blue light.
Reducing time spent on devices wherever possible would also help.
Do you think about how you use and consume light? We live in a culture where electricity and artificial light are everywhere: inexpensive and always available in seemingly endless supply. We're so used to being surrounded by light -- it's truly at our fingertips -- that many of us don't even think about it, much less question the timing and degree of our exposure. Yet a robust and growing body of scientific research suggests that for the sake of our sleep -- and our overall health -- we all need to start paying a lot more attention to the presence of light in our daily lives.
How did we get here? After all, nearly all of human history has unfolded without electricity, and without the near-constant presence of artificial light. In the roughly 125 years since the advent of electricity, nearly every aspect of human life has been fundamentally altered. Unlike our ancestors, we're no longer expressly tied to the solar day and night or to the long and short light of the changing seasons. With the flick of a switch, we can experience "daylight" or "summer" at any time. Artificial light has enabled transformative change to the way we live, work, and play, the way we engage in relationships and community. Society and culture may have adapted readily and even voraciously to that transformative change. But our bodies have not. The widespread emergence of artificial light has ushered in new risks to health, risks our pre-electricity ancestors never had to face.
Over the past two decades, science has increasingly turned its attention to exploring the effects of light exposure to human health. What was once a somewhat shaky scientific proposition is now widely accepted, if not yet fully understood: chronic exposure to artificial light, particularly at the wrong time of day, is dangerous to health. And sleep, which can be deeply affected by light exposure, is one critical piece of the puzzle.
How does artificial light exposure disturb normal, healthy sleep? It does so in large part by disrupting the body's natural circadian rhythms. Circadian rhythms are one of the two physiological systems that regulate sleep-wake cycles. (The other is the body's own, internal sleep drive.) Circadian rhythms exist in almost all living organisms, and are influenced primarily by exposure to light and darkness. Circadian rhythms operate on an approximately 24-hour cycle, essentially in line with the solar night and day. Our sleep -- as well as many other important biological processes, including digestion, hormone regulation, and immune function -- is deeply and fundamentally tied to these sensitive and finely tuned circadian cycles, which are in turn deeply influenced by both the presence and absence of light. Light exposure alters the ebb and flow in the body of the "sleep" hormone melatonin, which occurs in circadian rhythm. Melatonin levels naturally rise at night -- in response to darkness -- and play an important role in bringing about sleep onset. In turn, the natural early morning drop in melatonin levels helps prepare for wakefulness. Evening light exposure can delay the release of melatonin, causing a shift in circadian sleep-wake cycles.
Take a moment to imagine what life was like for people living before the widespread availability of artificial light. Even with supplemental light sources such as candles or oil lamps, the most powerful light exposure came from the sun. When the sun set, darkness appeared, largely without interference. That's no longer the case. When was the last time you experienced real darkness, with no street lights or city lights, no lamplight or overhead bulbs switched on after sunset, no television screens or computers lighting up the evening? Excessive exposure to artificial light in the evening hours -- which for most of us happens daily, often in abundance -- trumps the darkness that our bodies and circadian rhythms have evolved to expect and rely upon.
When circadian rhythms are disrupted by artificial light exposure at the wrong time of day, both the quality and quantity of sleep can suffer. Over time, the health complications from poor and insufficient sleep can be widespread, numerous, and serious. Poor sleep is linked to higher rates of anxiety, depression, and other mood disorders. Sleep problems are associated with increased incidence of cardiovascularand metabolic disease, as well as to problems with endocrine and immune function. Sleeping poorly may increase risk for cancer. Poor sleep is also associated with sharp increases in accidental injury and death, as well as in problems with memory andcognitive function. Nearly all measures of health, safety, and performance are negatively affected by a lack of regular and routine high-quality sleep.
What's more, there's a burgeoning body of scientific evidence indicating that circadian rhythm disruption is itself deeply harmful to health. Circadian dysfunction is linked toelevated risks for cancer, cardiovascular disease, diabetes and other metabolic disorders, as well as to psychological stress and depression.
Scientists have discovered that when it comes to sleep disruption and circadian rhythms dysfunction, not all light is the same. Different wavelengths of light appear to have different degrees of effect. In particular, blue spectrum light has been shown to be especially disruptive to sleep, and to circadian function. Blue spectrum light is found in higher concentration in some energy-efficient LED and fluorescent light bulbs. High concentrations of blue-wavelength light are also emitted from the LCD screens of digital devices. Studies show exposure to blue-spectrum light at the wrong time of day has a greater effect than other light spectra on suppressing the natural release of melatonin.
It is important to be clear: light exposure isn't uniformly or indiscriminately harmful. The dangers of light exposure occur largely in the timing and in the degree. That same blue light that can have such a negative impact at night can have beneficial effectswhen you're exposed to it during the day. Daytime blue spectrum light exposure (as well as light exposure in general) can boost alertness and reaction times, elevate mood, and help maintain healthy circadian rhythms. Receiving abundant light exposure during the day can strengthen and reinforce sleep-wake cycles and improve sleep when nighttime--and bedtime--arrives. The key to healthy light exposure is to understand how light can affects the body, and to be thoughtful and strategic about when and how you use it. We need light, and we can benefit from it in numerable ways. But we also need darkness.
It's time to start thinking about light as a powerful medicine -- capable of providing tremendous benefit when used correctly, but requiring care and education in that use. Like a potent drug, it's absolutely necessary that we stay educated and aware of all of light's possible effects on our brains and our bodies. Only then can we use light effectively and well, taking full advantage of its very real benefits while minimizing its dangers and risks to our health.
Sweet Dreams,
Michael J. Breus, PhD The Sleep Doctor™ www.thesleepdoctor.com
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