From Dawn Till Dusk: The Dangers of Blue Light

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For the greater part of human history the daily rhythms of life, like those of Nature herself, were tied to the trajectory of the sun. The pale light of dawn signaled the start of day while dusk marked a hurried return to homes or villages. Indoor fires and lighting were possibly dangerous, expensive and dirty. The relatively recent advent of electricity and the incandescent light bulb heralded rapid and radical changes in the rhythm of our days. No longer was human activity bound by the limits of natural sunlight. No longer were we required to work by day and sleep by night. Ceaseless daylight was born. Each of us could control our own personal sun in our homes and workplaces. Yet this apparent technological blessing, wielded with abandon while its full consequences were not understood, has instead become a bane to health and harmony.

THE DANGERS OF BEING BLUE

The problems with modern lighting, especially those that utilize the brighter, daylight spectrum, have not been understood until relatively recently, with our improved grasp of the connection between specialized cells in the human eye and how these affect intricately delicate and complex hormonal and other regulatory systems in our bodies.

According to Wikipedia, the photopigment melanopsin “is found in some retinal ganglion cells in the eyes of humans and other vertebrates. These cells. . . perceive light but are much slower to react to visual changes than the better known rod and cone cells. They have been shown to affect circadian rhythms, the pupillary light reflex, and several other functions related to ambient light. . . Evidence supports prior theories that melanopsin is. . . responsible for the entrainment of the central ‘body clock’ in mammals.”¹

Melanopsin appears to function by affecting and suppressing the production of melatonin, the hormone that allows us to anticipate darkness and signals the onset of sleep. Exposure to light in the evening thus interferes with various hormone-regulating systems, thereby affecting sleep, mood, energy and performance. Commenting on the effects of light on our health, one neurologist has stated that “light works as if it’s a drug.”² Indeed, just as food is medicine, so is proper light, and the lack of nourishing light, like the lack of nourishing food, causes harm.

The effect on sleep cycles and sleep quality is especially important. For instance, one study found the use of an iPad at night before bed caused the body to produce 55 percent less melatonin. Participants took longer to fall asleep and experienced less REM activity during sleep. (REM sleep is vital for modulating mood, handling stress, and activating learning capacity, among other benefits.) These same subjects experienced reduced alertness in the morning and had delayed circadian rhythms the next evening compared to those who had read a physical book before bedtime instead. ³ The good news about this biological mechanism is the relatively short spectrum length that affects melanopsin, only between 450 and 530nm. The bad news is this is exactly the spectrum of light predominantly produced by many techno-gadgets and energy-efficient light bulbs, such as CFLs and LEDs.

Thus, reducing exposure to and blocking out this spectrum during the evening is key to helping our bodies stay in healthy sleep cycles, creating conditions for restful sleep and good overall health.

MINIMIZE BLUE LIGHT EFFECTS

First, especially for city dwellers or anyone facing light pollution, light-blocking curtains are a must. The darker your sleeping quarters the better. A bedroom should be as minimally populated by technology as possible. No computers, no cell phones or iPads, no routers or wireless modems. Make your bedroom a protected haven and respite from the gadgetry of the modern world.

If you need a clock in your sleeping quarters, models are now available in red light and that only display when touched by you. Similarly, have a lamp or two in your sleeping quarters with specialized light bulbs that focus on the warm, evening light spectrum rather than the bright day range of color, such as those oh-so-evil incandescent bulbs. Go for lower wattage (less total light producing) bulbs as well as the warmer color spectrum, as the two combined help the body prepare for slumber and are less disruptive to our bodily rhythms.

Avoid CFLs (compact fluorescent lamp) Spring 2013). Go with LEDs. Though they typically skew towards the blue, you can look for ones that are specially made or coated to change the light balance for bedroom or similar use.

WAYS TO BENEFIT FROM BLUE LIGHT

Do note that blue light is not all bad news. It appears it is mainly harmful when our exposure comes at the wrong time. Especially for people whose work denies them access to sunlight, or people in climates and locations that have limited natural light, blue light exposure can be very beneficial. Astronauts, for instance, are given specialized lights that “encourage energy and activity during what would be daytime hours, and then (use)…light bulbs that dial back on the blue to boost astronauts’ production of melatonin for a good night’s sleep. Similarly, many people who live in the prolonged dark of northern winter climates are prescribed blue light to fight off SAD (seasonal affective disorder).”⁴

IF YOU CAN’T ESCAPE BLUE LIGHTS

A number of companies now make glasses that filter out blue light, along with other blue light-blocking accessories and gear. For those who must work late in the evening and cannot control the light of their environment, such glasses may provide benefits to their health and sleep.

PROGRAMS FOR TECH

For those who use computers and phones for work, especially in the evenings and thus have little choice save to change occupations, a few very useful options exist to help minimize exposure and damage from blue light, especially in the evenings.

F.lux is free, down-loadable software that automatically controls your computer’s color spectrum, causing the display to mimic daylight and warm night-time light at the appropriate times automatically. It is available for free for PCs and laptops. It can only be used on jailbroken phone devices. Find out more at justgetflux.com.

It is also important at night to drop the total brightness of your devices, not just remove blue light. A recent study showed that an area in the brain called the suprachiasmatic nucleus, or SCN, is affected by both intensity and color of light exposure.5 The SCN measures time for the body using chemicals and electrical rhythms.

So turn down the brightness as well. Note that distance matters with light. At six inches, you receive four times more light than at twelve, and sixteen times more light than at twenty four (light decreases over the distance squared, so every doubling of distance quarters the intensity). Especially for computers, the farther you are from the screen, the better for your body. Even better is to avoid technology for the last hour or so before bed each day. I know this is a radical idea, but instead you can chat with a family member or friend or read a book alone or aloud—both my wife and children prefer these options anyway!⁵

Turning down the brightness of all lighting in your home throughout the evening also helps you adjust to turning down gadget brightness. It is hard to have technology turned low if the ambient environmental light is strong and bright. Toning down the overall brightness helps everyone prepare for and enjoy better sleep.

BE IN THE LIGHT

Let me offer a few final recommendations. First, strive every day to spend time outdoors in direct, natural light. If you work an office job, take your lunch break outdoors, somewhere with unimpeded sunlight. If it means the roof of your workplace, so be it! If you absolutely can’t do this, make sure that your work environment and indoor environment exposes you to the right kinds of light at the right times if you are able, such as an eastern window in the morning. A recent study showed that people exposed to natural light during the work day experienced significantly longer and better sleep than those whose work denied them such light.^7,8

Second, some studies have shown that for people with significant sleep cycle and quality troubles, escaping to a natural light environment with no technology or gadgets for about a week can significantly improve sleep and reverse some of the damage done by badly timed light. So try on a regular basis to go camping or otherwise escape into nature to help keep your body better in tune with the natural cycles that governed our work, rest, and sleep for thousands of years.

Do what it takes to promote and protect your health. Natural light helps your body properly regulate and maintain balance with natural circadian rhythms. Exposure to direct sunlight improves melatonin levels and shifts the hormone to function more in line with an early-to-bed and early-to-rise schedule. And as we know, “early to bed, early to rise, makes people healthy, wealthy, and wise.”

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SIDEBARS

STUDIES ON LIGHT.¹¹
In one study men exposed to fluorescent lights produced 40 percent less melatonin and reported feeling more awake an hour after the lights were shut off for bedtime than men exposed to incandescent lighting.

Another study showed that light exposure delayed the onset of melatonin production by as much as ninety minutes after the lights were turned off.

Yet another study involving mice showed that those exposed to light at night gained more weight than those exposed to normal amounts of daylight, even though both groups consumed identical amounts of calories.

The WHO has stated that “shift work” is a probable carcinogen, especially for breast cancer. This is perhaps partly attributable to the disruption of basic natural rhythms, and also to the fact that most of these jobs are performed under intense, artificial fluorescent lighting.

For those with severe sleep and circadian rhythm disturbances, it may be time to go on an extended camping trip where modern technology is strictly limited to help the body reset and regulate itself to more natural and healthy rhythms.

LIGHT UP YOUR LIFE SAFELY
A small number of studies suggests that there is possible danger that the blue portion of the light spectrum which LEDs in particular produce (though CFLs do as well) may cause irreversible damage to our eyes.^9,10 I commented on this issue at length in the Letters section of this journal (Spring 2015), but will briefly restate points below. Remember, damage to the eye is based on light spectrum, intensity, duration of exposure, and likely the health status of the one exposed. To help minimize possible damage attend to these pointers:

1. Eat a nourishing diet, rich in vitamin A and antioxidants. Avoid polyunsaturated fatty acids and processed foods.
2. Turn down the brightness on your devices and use lower-wattage ambient light when possible. Bring in as much natural light into your living and work spaces as possible. Realize that no light bulb was ever designed to be looked at directly. They are made to help you to see, not to be seen.
3. Sit as far away from electronic devices as possible. Seek to have your eyes at least twenty-four inches from computer and other gadget screens (farther for TVs, especially large TVs).
4. Take regular breaks when working with technology. Plan a five- to ten-minute break every thirty minutes and a shorter break every ten to fifteen minutes to rest your eyes and give them time to recover.

REFERENCES
1. en.wikipedia.org/wiki/Melanopsin
2. nytimes.com/2011/07/05/health/05light.html?_r=3&pagewanted=all&
3. pnas.org/content/early/2014/12/18/1418490112.full.pdf+html
4. cnet.com/news/nasa-lightbulbs-come-down-to-earth-and-into-your-house/
and http://www.wired.com/2015/03/artificiallight-may-be-unhealthy/
5. (news.sciencemag.org/biology/2015/04/colors-help-set-bodys-internal-clock?rss=1).
6. (news.sciencemag.org/biology/2015/04/colors-help-set-bodys-internal-clock?rss=1).
7. aasmnet.org/jcsm/ViewAbstract.aspx?pid=29503
8. scientificamerican.com/article/trouble-sleeping-go-campi/
9. upi.com/Science_News/2013/05/11/LED-lights-ruin-retinasresearchers-say/UPI-52041368287606/
10. electronicsweekly.com/news/components/led-lighting/ensuring-safety-in-led-lighting-2012-11/
11. For an extensive list of studies related to this topic, you can visit justgetflux.com/research.html

 

This article appeared in Wise Traditions in Food, Farming and the Healing Arts, the quarterly journal of the Weston A. Price Foundation, Summer 2015

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