For essentially all of human existence until really about a century or so ago, the sun was our main and really only source of consistent light. The arrival of the sunrise and sunset each day were a signal to our bodies that it was either time to wake up and be alert or begin winding down to rest. However, over time as the invention of blue light emitting devices like fluorescent and LED bulbs, televisions, computers and smart phones have made their way into our homes and replaced the darkness or soft glow of a candle with blue light, we have become at greater and greater risk of disturbing this natural bodily rhythm.
Now don’t get me wrong, blue light isn’t something we should be avoiding all together. It is something our bodies need and benefit from in appropriate doses. That said, the sun is actually the largest source of blue light. And blue light is even responsible for what makes our sky look blue. Because blue light rays have a shorter wavelength, they are higher energy. For us, this means that this light source can and does help boost our energy, alertness and even mood. And because of this it DOES serve an important function in our circadian rhythm.
However, while blue light serves an important function in this rhythm, too much of it, particularly in the evening hours, can disrupt it. When the sun goes down and darkness settles in, it triggers our brains to begin releasing melatonin – a hormone that regulates our sleep/wake cycle. But when we spend our evenings in well lit rooms and in front of our screens, it can actually be sending an unwanted message to our pineal glands to suppress this hormone, often leading to less and lower quality sleep. Studies show that not only does this affect the time our bodies have to do things like balance hormones, repair muscles and cells, strengthen our immune systems etc, but it also MAY be a contributing factor in diseases like cancer, diabetes and more.
While this day-in-age, it’s hard to eliminate all sources of blue light in the evening hours, the following are a few ways we can seek to reduce our exposure:
1.Turn off blue-light emitting devices 2-3 hours before bed. This is especially important for kids with developing brains. If children are going to be working on an iPad or watching a television show it would ideally happen during the morning or early afternoon hours, not near bedtime.
2. Use blue-light-blocking glasses and device settings to your advantage. If and when you need to work later into the evening, as I sometimes do, I recommend wearing a pair of blue-light-blocking glasses to filter the blue-light. These can easily be found on many popular sites like Amazon, Target etc. This is the pair I use at the moment – nothing fancy, but they do the trick.
If you don’t own a pair of these yet, there are few other things you can do to mitigate the effects immediately as well. First, turn the brightness down at night on the device you are utilizing so that it reduces the amount of blue light hitting your eyes. Also, for newer devices these days, you often have the option with the settings to select a “nighttime mode” which shifts the color of your display to warmer colors in the evening hours. On the iPhone or iPad this can be found by heading to Settings –> Display and Brightness –> Night Shift. On an Android device head to “Settings” App –> Display –> Night Light.
3. Use smaller devices at a greater distance from your eyes. Ideally we wouldn’t be using devices in the bedroom at all, but if you need to check a quick email or set a last minute reminder at bedtime, try and aim for using the smallest device possible ie. your iPhone vs. iPad. Larger devices have the potential to have a greater impact on us than smaller ones because they emit more light. Furthermore, the closer the device is to our eyes, the greater the light they will take in, so the further you can hold the device from them the better.
4. Opt for lamps and lights that offer warmer tones. As I shared previously, devices aren’t the only blue-light emitting culprits – light bulbs can and do too. When selecting a light source for your bedroom opt for warm-colored lightbulbs in your bedside lamps, smart bulbs where you can program settings by the time of day or speciality lamps like Himalayan Salt Lamps that offer a soft orange glow along with numerous other benefits. If you aren’t in the market to swap out bulbs at the moment, you can still do yourself a favor by ensuring the your bedside lamp is strategically placed behind your head vs. in your line of vision so that that glow you need to read your book in bed has the least amount of impact as possible on your melatonin production.
The Bottom Line…
In summary, when we are talking “blue light” and circadian rhythms it really just comes down to timing. Blue light does serve an important purpose, and when we are talking lightbulbs and devices it has even made for many an enhancement in the way we go about and conduct work and beyond throughout our daily lives. But like many a good thing, its also good to know when to “set it aside” so that not only can we rest our eyes and minds, but give our bodies the opportunity to rest and sleep the way they were designed to so that they can do their job in keeping us healthy and functioning at our best.
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