Blue light: how it shapes our sleep
It is difficult to conceive of modern life without our beloved screens. As we get further into fall and the weather continues to cool down, we likely will be spending more time indoors—studying, working, watching movies. From our phones and laptops to our TVs and tablets, most of us spend large chunks of time bathed in their light. And the problem extends to our energy-efficient new bulbs; LED and fluorescent lights. According to a UCLA study, people are spending 13 hours a day in front of screens. But that light is not just light—it’s blue light, a high-energy wavelength that can affect our health in several different ways.
According to the Indian Journal of Ophthalmology, children have even less ability to filter the short wavelength of light, and suffer at proportionately higher rates than adults, with eye strain, headaches, and longer-term health results. Harvard Health Publishing reported that our excessive basking in blue light, “…may contribute to the causation of cancer, diabetes, heart disease, and obesity.”
In small quantities, it is natural to be exposed to blue light, even required for our overall health. The sun, which produces a combination of all colors in the visible spectrum, is our biggest source of blue light controlling our internal clock, or circadian rhythm and, thus, telling us when to wake and sleep. Exposure to blue light during the day keeps us awake, boosts mood, and might even assist in memory and cognitive function. The issue is when blue light lingers in the evening, due to the use of our electronic devices.
OUR DIGITAL DEVICES operate like a lens and focus short wavelength, high energy blue light directly into our retinas.
Drawing by Priscilla Duggan
We are hardwired to respond to light as a signal of time. When blue light enters the eyes after sunset, it suppresses melatonin, the hormone that signals to the body, “It’s time to sleep.” The result? Tossing and turning when we’d rather be relaxed and drifting off. As most readers probably know, disrupted sleep can ripple into other areas of health, affecting mood, immunity, and even metabolism.
But hold off on worrying about your late-night reel scrolling or Netflix binging just yet: awareness is where we begin, and small changes can make a big difference. Here are some friendly suggestions for working with—rather than against—blue light:
Set a screen curfew. Try putting devices down at least an hour before you go to bed (two or three hours would be optimal in order to give your body proper time to settle). If that’s not doable, even 20 to 30 minutes of screen time-free can be helpful.
Use night mode. Most devices have a “night shift” or “blue light filter” feature that makes the screen’s color redder after nighttime, minimizing your exposure to blue light.
Try to get some real light exposure every day. Going outside during the day—ideally in the morning—is an excellent way to build up your circadian rhythm, so that it’s easier to sleep at night.
Consider blue-light blocking glasses. They’re not for everyone, but for shift workers and anyone who is just staring at screens all evening, they can be useful. Another idea is a screen protector that lowers blue light emission, and keep interior lighting dimmed (or use candles—just kidding).
And, as with most problems of our contemporary era, the issue isn’t blue light, but balance. We can think of our exposure to light as yet another cycle to honor. Sun by day, soft light by night—that’s what our bodies were meant to expect.
So as we head into November, when days shorten and nights draw out longer, experiment with how you light your life. Maybe dim the lamps after dinner, substitute scrolling with a book, or take a morning walk to get a little natural light. By doing that, you’re not only saving your eyes, and maybe your health in general—you’re giving your entire body a chance to restart.
After all, health is not about getting rid of the comforts of modern times, but finding a rhythm that fosters rest, resilience, and a bit more ease in our lives.
Category: People
