As we all continue to spend more hours every day in front of a screen—whether it’s a smartphone, tablet, computer, or TV—health experts are warning that too much exposure to the artificial hue of light from electronics after dark could be bad for our health.
Experts say that overuse of electronic devices can be particularly harmful in the evening hours, when our bodies are supposed to be winding down for rest.
But just how much screen time is “too much?”
And if you must be in front of a computer for hours on end for your job or other lifestyle reasons, is there anything you can do to mitigate the effects of this artificial lighting on your health?
We’ll answer these questions and more as we dive into the controversial topic of light pollution and the effect of nighttime screen lighting on your health.
What type of light is considered “artificial lighting?”
Artificial light at night is discussed so frequently in modern scientific literature that it even has its own abbreviation in academic journals—ALAN. ALAN is understood to negatively affect circadian rhythms as well as causing other, more serious, health disruptions. ALAN is also referred to as light pollution, and can have profound impacts on the health of humans, animals, and plants.
The advent of in-home, on-demand electricity has fostered in an era of rapid change and development, and humans have ushered new electronic devices emitting a variety of different light frequencies into our daily lives at break-neck speed.
With the increasing popularity of energy-efficient light sources such as LEDs, the desire for “whiter light” continues to push the spectrum towards the blue tones in the color wheel, which moves farther away from the warmer hues found in nature.
How much screen time is “too much?”
The primary concern with artificial light at night (ALAN) is that it has introduced unnatural lighting sources at intensities, hues, and timeframes at which they do not occur in nature. This can be in the form of security lighting, advertising lighting, street lighting, and much more. However, the average person experiences this most often in the form of screens in their own home each evening.
A quick experiment to see how this phenomenon affects you personally (be honest!): Is your smart phone in your pocket or your hand right now as you’re reading this article? If not, how many inches away from you is it? And how many minutes has it been since the last time you looked at it?
We could take that exercise a step further and ask how many hours of television viewing or computer reading do you take part in each evening after the sun has gone down, but you probably get the idea by now—this issue affects all of us. In fact, a whopping 95% of people surveyed by the National Sleep Foundation in 2011 admitted they used electronic devices within the hour before bed. As little as 100 years ago, this amount of artificial light was not normal for anyone, let alone everyone.
Additionally, the spectrum of light introduced by ALAN is totally different than the natural spectrum of light available from sunlight, moonlight, or starlight. Since the lightwaves emitted by LED and other electronic light are on a (literally) different wavelength than what existed for thousands of years prior, scientists have been studying what possible biological changes are being caused by this relatively new phenomenon of electronic light at night.
The research findings about ALAN’s health effects thus far have been fascinating. You may already have learned from experience that exposure to artificial bright light at night interferes with the body’s natural circadian rhythm, makes it harder to fall asleep, and increases overall alertness. But did you know that this shifting of your circadian rhythm caused by ALAN can impact your health on deeper levels, ranging from heart disease, to metabolic function and even breast cancer risk?
A growing body of research has shown the link between ALAN’s disruption of our circadian rhythms and the onset of cancer, heart disease, diabetes, and obesity.
So if the consequences of exposing yourself to artificial light at night are so concerning, what can you do to decrease your (seemingly) total dependence on electronics as a part of your evening routine?
How to reduce your exposure to artificial light
1 | Reduce screen time after 7pm
Starting with a specific, actionable goal is an important first step to reducing the light pollution you experience each day.
If your current screen time runs past the 11 o’clock hour every day, try to reel it back to 10pm each night. Once you achieve that and stick with it for three weeks, pull it back to a 9pm screens-off time. Gradually push the time earlier and earlier until your screens are shut off as close to the natural sunset hour as possible.
This encourages your body to align itself with the timing of the earth’s natural light sources, which is helpful from your body’s sleep as well as hormonal balance.
2 | If you must use TV, computer, or smartphone in the evening, wear tinted glasses while viewing it
Some of you may work odd hours, be up late at night with a little one, or just can’t part with your Friday late night movie tradition.
That’s ok! There are ways that you can use screens after dark and still protect yourself from some of its negative effects.
Wearing red-tinted glasses when using artificially-lit screens after dark is one way to bring the bluish hues back to a more natural tone as they are processed by the eyes. You can use something as simple as a pair of orange or red toned sunglasses, or go all-in and get a pair of glasses specifically designed for nighttime screen use which have a full wrap-around lens so that no ALAN get get to your eyes.
3 | Use salt lamps and other red-hued lamps after dark to avoid blue light
For lighting sources that are not a screen, you can still reduce the amount of blue tones you have in your home by switching out your CFL- and LED-lit lamps for red toned lights like Himalayan Salt Lamps.