Light and darkness balance is extremely important for our well-being as it affects our sleep. Exposure to light influences hormone production and disrupts our circadian rhythms which will impact our sleep.
- Blue Light and Melatonin Suppression: Exposure to bright blue light, especially from electronic devices like smartphones, computers, and televisions, can suppress the production of melatonin, a hormone that helps regulate sleep-wake cycles. Melatonin is typically released in the evening when it gets dark, signaling to the body that it’s time to wind down and prepare for sleep. However, exposure to blue light, especially close to bedtime, can interfere with this process and make it harder to fall asleep.
- Circadian Rhythm Disruption: Our bodies have an internal biological clock known as the circadian rhythm, which is synchronized with the 24-hour day-night cycle. Bright light exposure, especially during the evening, can disrupt the circadian rhythm and confuse the body’s internal clock. This can lead to delayed sleep onset, difficulty waking up in the morning, and overall poor sleep quality.
You may think that sleep is something that happens when you put your head on the pillow. In reality, sleep is part of a whole-body process that is related to other activities throughout the day and perhaps for longer periods if you take into account sleep debt, however, let’s focus on sleep as a part of the sleep-wake cycle over the course of 24 hours in different environments.
There is an extensive body of research looking at light as the key factor for the body’s biochemistry in terms of sleep.
How does light exposure throughout the day affect sleep?
Light exposure throughout the day is crucial in regulating the body’s circadian rhythm, which governs the sleep-wake cycle. The circadian rhythm is influenced by external cues, primarily light and darkness, and helps align our internal biological processes with the 24-hour day-night cycle.
By using light to alert our bodies to the environment we can improve the quality of sleep towards the end of the day when we are supposed to rest.
Here’s how light exposure at different times of the day affects sleep:
- Morning Bright Light: Exposure to bright natural light, especially in the morning, is essential for setting the body’s internal clock. Light exposure in the morning helps suppress the production of melatonin, the hormone that promotes sleepiness and signals the body to be awake and alert. It also helps synchronize the circadian rhythm, making it easier to fall asleep at night and wake up feeling refreshed in the morning.
- Midday Light: Getting exposure to natural light during midday can help reinforce the body’s alertness and energy levels. Sunlight exposure during this time can improve mood, focus, and overall well-being.
- Bright Light on Cloudy Days: Even on cloudy days, outdoor light is typically much brighter than indoor light, making it beneficial for regulating the circadian rhythm. Spending time outdoors on cloudy days can still provide adequate light exposure to support a healthy sleep-wake cycle.
- Artificial Bright Light: In the absence of natural light exposure, using bright artificial light can help simulate the effects of natural light. Light therapy devices, such as light boxes or dawn simulators, emit bright light to help wake you up in the morning and set in motion the mechanisms of the circadian clock. This can be particularly useful in the winter when less natural light is available.
- Limiting Light Exposure Before Bedtime: On the other hand, exposure to bright light, especially from electronic devices like smartphones, tablets, and computers, close to bedtime can interfere with melatonin production and make it harder to fall asleep. The blue light emitted by these devices is particularly disruptive to sleep. It’s best to limit screen time before bed and create a dim and relaxing environment to promote sleepiness.
By strategically using light exposure throughout the day, individuals can optimize their circadian rhythm and improve sleep quality. Incorporating bright light exposure in the morning, especially at the right angle, and avoiding bright light before bedtime can help regulate the sleep-wake cycle and promote restful and refreshing sleep at night.
Creating a darker environment for better sleep
To create a darker environment where you sleep, here are some effective strategies:
- Thicker Curtains or Blackout Shades: Install thicker curtains or blackout shades designed to block out external light. These can significantly reduce the amount of natural or artificial light entering your sleeping space. Look for curtains or shades specifically labeled as blackout or room-darkening to maximize their light-blocking capabilities.
- Use Eye Masks: If your current curtains or shades do not sufficiently block out light, consider using an eye mask. Eye masks create a personal barrier of darkness and can be especially helpful if you’re sensitive to even small amounts of light. Choose a comfortable, adjustable eye mask that fits snugly and blocks out as much light as possible. Many people find eye masks uncomfortable through, so prioritize getting the room darker by other more conventional means.
- Seal Gaps and Entrances: Check your bedroom for any sources of light leakages, such as gaps around windows, doors, or vents. Seal these gaps with weatherstripping or light-blocking materials like foam strips or adhesive tapes. Ensure the door closes properly and consider using a door sweep or draft stopper to prevent light from seeping in.
- Minimize Electronic Light: Avoid using electronics that emit light, especially in the hour or two leading up to bedtime. This includes televisions, smartphones, tablets, and computers. Even when switched on, the screens emit blue light that can suppress melatonin production and disrupt sleep. Instead, relax by reading a book, listening to soothing music, or practicing a calming bedtime routine. Meditation before sleep has been found to be beneficial.
- Dim the Lights: Lower the overall brightness in your bedroom in the evening to signal to your body that it’s time to wind down. Use dimmer switches, lower-wattage bulbs, or install warm-toned lighting fixtures to create a more soothing atmosphere. Avoid bright overhead lights and opt for softer, ambient lighting before bed.
Remember that creating a darker sleep environment involves a combination of physical adjustments and behavioral changes. Consistency is key, so make these practices part of your nightly routine to optimize your sleep environment and promote better sleep quality.
Using modern technology to limit light exposure
Smart devices and smart home solutions that offer a dark mode or programmable light settings can be very useful for maintaining adequate levels of hormones responsible for sleep.
Let’s dive deeper into practical applications of science to improve our lives:
- Dark Mode and Sleep-Friendly Lighting: Dark mode on smartphones and other devices changes the screen’s color palette to use darker colors, minimizing the amount of bright blue light emitted. This can be particularly useful during the evening when exposure to blue light should be reduced to support the body’s natural sleep-wake cycle.
- Programmable Smart Lighting: Smart home solutions that allow you to program and control the intensity and color of lighting in your home can be beneficial for sleep. By gradually dimming the lights in the evening and using warm, amber-colored light, you can mimic the natural progression of daylight and create a sleep-friendly environment. Smart lighting systems can be set to automatically adjust the light based on the time of day, helping to promote melatonin production in the evening and support a restful night’s sleep.
- Sleep-Enhancing Features: Some smart devices and lighting systems come with specific sleep-enhancing features. For example, they might offer a “bedtime” mode that gradually dims the lights in your bedroom, simulating a natural sunset. This can signal to your body that it’s time to wind down and prepare for sleep.
By utilizing dark mode and programmable smart lighting, individuals can reduce their exposure to blue light in the evening and support their natural sleep-wake cycle. Creating a sleep-friendly environment with reduced exposure to bright light can help improve sleep quality and overall well-being. As technology continues to evolve, incorporating sleep-friendly features in smart devices and home lighting systems can be an important step in promoting healthy sleep habits in our modern, technology-driven world.