Normally when we think of sleep, we think of darkness. Today we are going to learn about light (and darkness) and how it relates to sleep. Different types of light affect us differently when it comes to sleep. Let's jump right in.
1. Natural Light.
Ah, the good old sun. Important for so much of the life on our planet. It is also responsible for our sleep (indirectly). Sunlight helps to keep our circadian rhythms in balance. What’s a circadian rhythm? Let’s back up a bit.
Back in the pre-electricity days, the sun would go down, it would be dark, and people went to sleep. When the sun came up, it got bright, and they woke up. Circadian rhythms tell the body and brain that when it is dark outside, it is time to sleep. And when it is light out, it is time to wake up.
Exposure to the sunlight in the day keeps our circadian rhythms, sometime called our biological clock, in equilibrium.
Think of it as syncing your devices every time you come into contact with a Wi-Fi signal.
Your body will sync with the daylight, and when it becomes nighttime, your body starts preparing itself for rest. If you could spend the whole day outside, that’d be great. However, that is often unrealistic for most people.
But, if you can get natural light exposure at least 30 minutes a day, this can help your sleep. Even better would be exposure in the morning, middle of the day, and towards the end of the day.
Natural light exposure helps maintain a healthy sleep-wake cycle.
Remember when we talked about getting some sort of physical activity in during the day? Doing it outside is a double whammy. You get the activity AND the light exposure at the same time.
If you are unable to get sufficient sunlight, there are special lamps you can buy. In a later post we may cover these in more depth.
2. LED.
While exposure to sunlight is good for our sleep, LED (or light emitting diode) is not. Light exposure from our TV screens, phones, computers, etc trick our brain into thinking it is sunlight. This messes with the circadian rhythms and makes it difficult to sleep because your brain, in a way, thinks it’s time to stay awake.
Have you ever just kept watching movies, or binge watching shows all hours of the night, even when you were tired? Or stayed up playing computer, phone, or video games, despite feeling exhausted? Certainly some of this is the entertainment value, but also, it’s the light exposure. It lets you justify that one more episode, or just to the next checkpoint.
I’m all for screened entertainment in the evening to relax. But if you want to sleep better, turn the devices off at least one hour before bed. If you have to have some sort of electronic stimulation right before, watch TV (not TV on the computer, but the actual television set) with the incandescent lights on. Don’t sit in a dark, but glowing room.
Better yet, turn it all off and read a book (but not in bed!).
3. Darkness.
It’s important for you to control your exposure to light when you sleep. Ever fall asleep with the lights on? I’m betting you didn’t sleep the night. More likely, you woke up part way through the night, even if only to shut the lights off. Bright lights can interrupt the body's natural sleep pattern.
Some people can’t fall asleep if there is too much light. Again, this goes back to our pre-electricity days, where when it was dark, it was time to sleep. Certainly, the darker you can make your room, the less likely light will wake you up.
If you have an alarm clock with bright numbers, turn it on its face or against the wall. The light could affect your sleep. Also, if you wake up in the night, and see the time, you may develop anxiety about what time it is vs when you need to be up. This anxiety will make it difficult to get back to sleep. If you wake up, don’t know what time it is, but see it is still dark, you will more likely fall back to sleep, and quickly.
If you are prone to waking up at night to use the bathroom, use night-lights. Leaving a hallway or bathroom light on may be too bright, and not allow you to fall asleep as quickly after returning to your bed.
Remember: Control your exposure to light. Darkness is a cue for your body to sleep.
That's all for today. Happy Zzz's...