“Simply put, when you get more sunlight exposure during the day, and less light exposure at night, you’re on your way to a magic sleep formula that really works.”

― Shawn Stevenson, author

A balanced diet, exercise, and quality sleep are essential for mental, emotional, and physical health. Several factors influence these elements, but did you know that day and nighttime lighting can significantly impact your sleep quality? Today, we’ll look at how lighting affects sleep quality and offer advice on optimizing your bedroom lighting to create a more restful sleep environment.

The Science of Light and Sleep

Light influences our circadian rhythm, the physiological processes all living beings experience within a 24-hour cycle. It’s our internal clock that walks us through our day-to-day activities. A consistent circadian rhythm is important because it signals our minds and bodies that it’s time to wake up when it’s light and rest when it’s dark.

How Does Light Affect Sleep?

Light impacts the transition between two sleep phases: Non-REM and REM sleep. Non-REM sleep has four stages, which we transition through before reaching REM sleep. Each cycle lasts about 90 minutes. We achieve good sleep by going through four to six sleep cycle waves and getting six to nine hours of sleep.

Thus, it’s not the length of time we sleep but the number of sleep cycles we experience that helps us feel refreshed each morning. While it’s common to sleep through each transition, light exposure can cause us to wake up and start the sleep cycle over, thus disrupting our sleep.

Our body’s production of melatonin, a sleep-inducing hormone, is also affected by light. When our circadian rhythms are interrupted due to light exposure, our melatonin levels fluctuate. Too much light can cause a delay in sleep onset because our bodies won’t release an adequate amount of melatonin. Darkness amplifies the body’s response and increases melatonin to help you fall asleep more easily.

What Types of Light Affect Sleep?

Natural and artificial light are the two main types of light that influence our circadian rhythms and impact sleep. Spending time outdoors during the day and allowing natural light indoors in the morning has been shown to improve circadian rhythms. However, using screens in bed or for an hour or two before bed negatively affects our sleep quality, mood, memory, and concentration.

Natural Light and Sleep Quality

An article published in the National Library of Medicine notes that natural daylight at high intensities is beneficial in three ways:

• Advances the timing of sleep to earlier hours: More exposure to natural daylight increases the chances of falling asleep earlier in the evening as long as exposure to artificial light is limited.
• Affects the duration of sleep: Longer exposure to natural daylight increases melatonin production, which helps us sleep better through the night.
• Improves sleep quality: As little as 30 minutes of natural daylight can have an impact, and when combined with exercise, sleep quality improves even more.

Tips for Incorporating Natural Light into Daily Routines

Morning is the best time to get out and soak in natural light. Whether you prefer a walk through the neighborhood or sipping a warm cup of coffee on your patio, take advantage of daylight first thing in the morning and set yourself up for success throughout the day. Don’t worry if it’s cloudy; filtered light is still beneficial!

Routine activities that get you outdoors can be a great way to get exposure to natural light. Water your plants. Take your family to a park. Play with your pets. Go kayaking. Start (and finish) an exercise routine. Do something that brings you joy—as long as it’s outdoors.

It’s also important to be safe outside in the sun, so follow these guidelines to get the best benefits:

• Spend time in the sun within the first hour of waking up.
• Plan for at least 30-45 minutes outdoors each day.
• Don’t wear sunglasses, visors, or blue light filters outdoors.
• Get direct sunlight, not light filtered through windows.
• Use sunscreen with an SPF of at least 30 for skin protection.

Artificial Light and Sleep Quality

We’ve learned that artificial light, particularly during the evening and at night, can disrupt our circadian rhythm. Artificial light exposure can also contribute to circadian rhythm sleep-wake disorders (CRSWD). The two most common CRSWDs are jet lag and shift work disorder. In addition, studies have found that exposure to artificial light at night negatively affects our health and can increase the risk of:

• Sleep disorders
• Depression
• Obesity
• Diabetes
• Heart disease
• Cancer

Evening and nighttime artificial light exposure suppresses melatonin production. Our bodies need melatonin’s antioxidant properties because it induces sleep, boosts the immune system, lowers cholesterol, and ensures the thyroid, pancreas, ovaries, testes, and adrenal glands function properly.

In particular, blue light at night can have an extremely detrimental impact on our health and sleep quality. Blue light often comes from LEDs in outdoor lighting and screens like phones, tablets, computers, and TVs. You can limit your family’s exposure to blue light and increase the chance of a better night’s sleep if you follow these suggestions:

• Power down your electronics: Turn your TV, laptop, and phone to “night mode” and limit your blue light at least an hour before bed. When your electronics are in “night mode,” they will have yellow screens instead of blue and won’t distract you before bedtime.
• Take temptation out of the equation: Turn your bedroom into a worry-free zone. Keep your phone and other screens out of the bedroom so you aren’t tempted to check anything in the middle of the night.
• Use a sleep app or filter: Apps that promote good sleep are becoming increasingly popular. You can also go a step further and schedule your phone to shut down or install an app to filter out the blue light for you.
• Sleep in total darkness: Set yourself up to sleep better using blackout curtains or a sleep mask.

When you need artificial light in your home during the day, choose low-wattage lightbulbs between 45 and 50 watts, which should provide ample safety. You can also consider using smart lightbulbs that change color throughout the day and project yellow or amber light for evening and night.

Creating a Sleep-Friendly Environment

Is it possible to use light in a healthy way in the bedroom? Yes, by optimizing lighting in the bedroom for better sleep. Lighting comes in various types, and a good strategy to bring sleep-friendly lighting into your bedroom is layering. Consider these bedroom lighting tips to provide ample light—day and night:

• Ambient Lighting: Ambient lighting is natural lighting from windows or artificial lighting that illuminates your entire space so you can complete daily tasks. Ceiling fixtures and floor lamps are popular types of ambient lights.
• Task Lighting: Task lighting is standard for activities that require more concentration. If you read in bed at night or work at a desk in the corner of your room, you might have a task light to help you focus. Task lights come in several types, including desk lights, table lamps, swing-arm lamps, sconces, and wall-mounted lights.
• Accent Lighting: This source of lighting draws attention to or highlights a feature, often with a warm glow. Recessed lights, wall sconces, and tape lights are popular accent lighting types in bedrooms.

Dimmer switches and lightbulbs can control the amount of light in the bedroom, allowing you to use bright light during the day and a lower light before bed and during sleep. Make sure you look for lightbulbs compatible with an existing or new dimmer switch, as some Compact Fluorescent and LED bulbs aren’t.

Again, it’s important to reduce exposure to electronic devices that emit artificial blue light—especially one hour before bed. Consider creating a tech-free bedtime routine so your family winds down by reading books, meditating, or listening to music. You can also set a “curfew” for electronics at a certain time so everyone turns their screens off before their bedtime. Your entire household will sleep better in the long run!

Now that you know how lighting impacts your sleep quality don’t forget to check the condition of one of the most prominent elements in your bedroom: your mattresses. If they’re not as comfortable or supportive as you’d like or are more than seven years old, it’s time to consider buying a new mattress. For more tips on creating a restful sleep environment, check out our guide to The Ideal Bedroom.