Good sleep depends on many factors, not the least of which is exposure to light. When your bedroom is too bright, you may struggle to fall asleep or even be disturbed in your sleep at night. Understanding how your circadian rhythm responds to light and learning how to manage light in your bedroom can help you sleep better at night.
How Light Influences Your Circadian Rhythm
Your circadian rhythm tells your body and brain when it’s time to start feeling tired and fall asleep, and likewise when it’s time to wake up and be alert. This rhythm isn’t arbitrary; it depends on cues from your environment and behaviors, including light, sound, and when you eat.
When you’re exposed to light, your circadian rhythm gets the signal that it’s daytime. And during the daytime, you should be awake. Although sunlight may more or less follow when you should be sleeping, artificial light can throw a wrench into sending the proper signal. Exposure to artificial light at night can tell your circadian rhythm that it’s daytime, even when it’s night.
Artificial light can come in the form of overhead lights or lamps, your television, or your mobile phone. It can even be street lights or car headlights shining through your window. Moonlight, though natural light, can also send a confusing signal to your circadian rhythm if it’s particularly bright.
Any kind of light exposure at night can have a negative influence on your circadian rhythm. Light exposure may make you feel too alert to go to sleep, especially if you’re exposed to bright light just before bed. And yes, that does include your mobile phone screen or TV. Bright lights that are on while you’re sleeping may even be disruptive enough to wake you up while you’re sleeping.
How You Can Manage Light in Your Bedroom
Ideally, your bedroom should be as dark as possible at night. Of course, that’s not quite practical, because you can’t get ready for bed and lay down on your mattress in pitch-black darkness. After all, an injury from falling over furniture on your way to bed might disturb your sleep more than exposure to light would. But you can limit your exposure to light at night, and especially in your bedroom. Here are a few ways to do it effectively:
- Design bedroom lighting with sleep in mind. Bright, overhead lights are common in bedrooms, and while they can be helpful during the day or early evening, they’re bad news for sleep at night. Turn off the overhead lights at night and instead use lamps pointed down below eye level to light the way once the sun goes down.
- Use dimmers. If you still want to use an overhead light but want to turn it down, consider installing a dimmer switch. That way, you can avoid bright light and just have a lower level of brightness at night.
- Block out window light. Moonlight, street lamps, headlights, and other outdoor light sources can come in through your window and disturb your sleep. Consider using blackout curtains so you can effectively block out light at night, then open them up during the day to get light exposure.
- Limit or eliminate electronics in your bedroom. Your mobile phone, TV, or laptop can be especially problematic for sleep when you use them at night. Checking your phone, watching TV, or even worse, working in bed – can keep you up at night. The blue wave light emitted from electronic screens is particularly stimulating and confusing for your circadian rhythm. Watch TV or work at night away from your bedroom, and never bring your mobile phone to bed. It’s best to put an end to screen time at least one hour before bed.
- Make sure you’re exposed to daytime light. Exposure to light at the right time of day is just as important as avoiding it at night. Daytime light exposure can reinforce the timing of daytime alertness so your time to be sleepy at night is on track, too. Open your window coverings in the morning for exposure to bright light and make sure you spend some time outdoors during the daytime every day.
Though it can sometimes be difficult to avoid light exposure at night, managing light in your bedroom typically has simple solutions. Do your best to avoid bright lights at night and shut down electronics well before bedtime to reinforce the right cues for your circadian rhythm and natural sleep schedule.
Amy Highland is a sleep expert and loves taking naps during thunderstorms and cuddling up with a blanket, book, and cats.