Sleep in the Dark
One of the secrets to a better night's sleep is a pitch-black setting.
Here's why:
How does darkness affect sleep?
Darkness is the primary cue that tells our bodies it's time to slumber. It's the chief controller that communicates with our internal clock, which is tucked away in our hypothalamus (brain). Darkness triggers the production of the sleep-inducing hormone, melatonin. As evening approaches and the light in our environment dwindles, the hormone melatonin begins to rise and our body temperature falls—both of which help us to become less alert and more likely to welcome sleep. With the help of morning light, melatonin decreases, body temperature begins to rise, and an uptick in the activating hormone, cortisol occurs to help us feel alert and ready for the day. This is a natural and healthy rhythm…and one of the many examples of how we are intricately connected to our external environment.
Does artificial light count?
Yes!! Our internal clocks aren't only sensitive to the rising and setting of the sun. Research shows that artificial light has a major impact on circadian rhythm and the production of sleep hormones. The thinking part of our brain that differentiates fake light from natural light isn't able to pass that tip along to the hypothalamus. Scientists at Tulane University studied melatonin production and found that sleeping in rooms with even dim lights caused melatonin levels to drop, affecting not only the ability to fall asleep but also to stay asleep.
A study in the Journal of Clinical Endocrinology & Metabolism concludes that exposure to room light before bedtime "exerts a profound suppressive effect on melatonin levels and shortens the body's internal representation of night duration. Hence, chronically exposing oneself to electrical lighting in the late evening disrupts melatonin signaling and could therefore potentially impact sleep, thermoregulation, blood pressure, and glucose homeostasis.”
How to achieve total darkness in the bedroom?
The first step is to survey your room for interior and exterior sources of artificial and natural light. You may be surprised. Keep a list and take action.
Here are some ideas:
1. Dim the lights before bedtime.
2. Eliminate electronics. Researchers have found that circadian rhythm is especially sensitive to light with short wavelengths, in particular the blue light given off by electronics, such as computers and cell phones, and also by energy-efficient fluorescent bulbs. “Blue light preferentially alerts the brain, suppresses melatonin and shifts your body clock all at the same time. Your brain is more alert now and thinks it’s daytime because we have evolved to only see bright light during the day,” says Harvard sleep researcher, Steven Lockely.
3. Avoid fluorescent lights in the bedroom.
4. Forget night-lights. Even dim lighting can suppress melatonin production. If you need a light to guide you in the middle-of-the-night, consider a motion-activated night-light.
5. Ditch the digital clock. The first thing I do when entering a hotel room is unplug or hide the bedside digital clock. At home, consider a good old analog clock. (And if you need to check the time while it's still dark, consider a clock with an illumination button rather than one that stays lit all night long.)
6. Use blackout shades. Light-blocking shades, blinds, and curtain liners keep street lights and car lights out of your bedroom. They also keep early morning light from waking you. It's best to have window coverings that block the light at night, but can be drawn during the day to bring the sunlight in.
7. Use an eye mask, if you can't make the room dark.
8. During the day be sure to get some sun. Exposing your body to sunlight not only helps alert the brain to produce the activating hormone cortisol, but also helps you sleep better at night because it keeps your circadian rhythm on schedule.
Sweet Dreams!