Why Your Lighting is Messing with Your Sleep (and How to Fix It)
Why Your Lighting is Messing with Your Sleep
Light is the most important factor in your ability to get a good night’s sleep. Humans are diurnal, meaning that we’re attuned to the sun’s cycle - we naturally wake and are alert when the sun is up, and when it sets, we go to sleep. But modern electricity presents a problem. Instead of winding down as the sun sets, people often turn on bright overhead lights, or they turn on the TV or a movie after dinner. What’s even worse for circadian health is that many people have the habit of scrolling on their phones as they’re winding down for bed at night. We’ve likely all heard at some point that this isn’t a helpful habit - but why? This consistent exposure to bright light or blue light wavelengths after the sun sets disrupts our body’s ability to sync with the cycle of the sun, otherwise known as circadian rhythm. In extreme cases, such as seen in people who work night shifts for extended periods of time, disrupted circadian cycles are correlated with a host of health issues, like weight gain, poor mental health, and cardiac issues. This is where understanding how light affects sleep becomes crucial. Understanding how light affects sleep is essential to creating a healthier home and improving your mood, energy, and rest.
Why Blue Light and Sleep Don’t Mix
Blue light in particular has the ability to disrupt our circadian rhythm. Blue light wavelengths activate specific photoreceptors in the brain that are sensitive to those wavelengths, tricking the brain into thinking it is being exposed to daylight. Our bodies then suppress the production of melatonin, a hormone that causes us to feel tired. Exposure to blue light, specifically at night, can keep us alert in the evening hours when we should be winding down to fall asleep. This is why there's growing awareness around blue light and sleep and its long-term effects on health and rest.
How Our Ancestors Slept: Natural Light and Circadian Rhythms
In our early history, the only alarm clock our ancestors had was the first rays of morning sun. When our earliest ancestors woke each day with the sun, soaking in those early morning rays gave their systems an anchor point on which to base the rest of the day. They experienced an early morning cortisol spike, which prepared their bodies for sleep later in the evening, and boosted their immune systems, metabolism, and ability to focus. Access to natural sunlight throughout the day increased their alertness and focus. Additionally, exposure to the more orange-y afternoon light served as a second touchpoint for their circadian rhythms, which then began to slow down and prepare for sleep. By the time the sun began to set, their bodies were ready for sleep, and they fell asleep quickly and easily.
How Light Affects Sleep in the Modern World
With modern electricity, however, most people in today’s day and age are out of touch with this rhythm. After Thomas Edison’s invention of the light bulb in the early 1880s, it took some time for houses lit by electricity to become widespread and common, so that most American households were lit with electricity by the late 1940s. In the 1960s, television sets were common in American households as well. Nowadays, it’s very common for people to turn on bright lights when the sun goes down, or to watch their favorite show or scroll through social media to wind down after a long day of work in the evenings. Unfortunately, they may not realize how light affects sleep or the ways in which artificial lighting overrides natural circadian cues, and how detrimental this is to their circadian health. Artificial lighting like overhead lighting, as well as electronic device lighting, uses blue light, which, in nature, tells our bodies that the sun is out and it’s early in the day, inducing alertness and wakefulness. After evolving to synchronize with the patterns of the sun, people’s natural circadian rhythms can become completely disrupted by habits of watching TV shows in the evenings, or scrolling through social media to wind down. They will experience trouble staying focused and alert throughout the day, and their risk of health issues like cardiovascular issues, poor mental health, and digestive problems will increase. People who engage in these habits might have trouble falling asleep each night, then will feel groggy, irritable, and unfocused throughout the following day. Fortunately, many of these effects can be mitigated with thoughtful bedroom lighting tips and adjustments to evening habits. If people who engage in poor nighttime lighting habits begin to pay attention to their bedtime habits and shift away from blue light exposure in the evenings, they will begin to notice a difference in energy levels, sleep quality, and overall mood.
Lighting Solutions: Simple Changes with Circadian Lighting and Other Tools
Our ancestors had no need for bedroom lighting tips as they aligned their days with the sun. But today, a little guidance on the best lights for sleep can help us re-align with natural rhythms. If your evening routine sounds similar to the modern living one described above, you’re certainly not alone, and a few small changes to your lighting can make a big difference. Consider the following bedroom lighting tips:
TIP #1: To support your circadian health, limit your exposure to blue light in the evenings. For example, use warm-toned lighting in your bedroom, which mimics the colors of a sunset and keeps us aligned with the cycle of the sun, instead of using fluorescent or blue-toned lights. Warm lighting is often included in guides for the best lights for sleep. Additionally, limit phone or screen usage before bed, but if you do use your electronic device before bed, enable night shift mode on your device, which will reduce the amount of blue light that your screen emits.
TIP #2: Another solution is to use blue light blocking or red tinted glasses. These types of glasses block blue light wavelengths, allowing your body to naturally prepare for sleep. For effective results, use red tinted glasses 2-3 hours before you plan to go to bed. If you're wondering how light affects sleep, tools like red-tinted glasses show just how sensitive our biology is to light input.
TIP #3: Consider using red light night lights in transition zones throughout your house, to guide your path if you need to be up in the middle of the night. The red light will help you stay drowsy, enabling you to fall back into a deep sleep quicker if you happen to be up at night.
TIP #4: For overall circadian health, prioritize spending time out in the sunlight each morning. Getting even 5 minutes of direct sunlight in the morning can boost your energy levels and improve your sleep quality later that night. Your circadian rhythm is regulated by sun exposure, and that intentional time in the sun can act as a point of reference for your body’s internal processes. If you don’t have access to early morning sunlight, or on dark or cloudy mornings, consider investing in circadian lighting for your home. Circadian lighting is high luminance lights designed to mimic sunlight, allowing you to gain the benefits of sunlight even on cloudy mornings or in west-facing apartments.
Sleep is foundational to well-being, and light plays a bigger role in a healthy night’s sleep than most people realize. By aligning your lighting choices with your natural circadian rhythm, you can create an environment that supports deeper rest and better health. Start with one small change tonight, and notice the difference it makes.
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