If you live in a city that never sleeps, does that mean you don’t get to, either? Some people struggle more than others with the effects of city noises and bright lights, but there’s no doubt they can make your sleep more fitful and make it harder for you to get as much shut-eye as you really need.
How noise affects sleep
Studies1 show that exposure to noise pollution during sleep has negative effects on health and significantly impairs sleep, affecting both its quality and duration.
In the lighter stages of sleep, the brain continues to process2 the sounds you hear, perhaps as nature’s way of staying alert to predators sneaking up on you during the night. So it’s not surprising that loud, startling sounds like sirens or honking horns may startle you awake. But background noise of any kind can cause you to sleep more restlessly3—moving, twitching and shifting rapidly between the stages of deeper and lighter sleep. You may wake up groggier, even if you don’t remember being woken.
How light affects sleep
Because our circadian clocks are so dependent on light,4 light pollution from streetlights, neon signs and illuminated buildings also have an effect on our sleep. The problem is that artificial light tricks us into staying up later than we would naturally. Without the ability to switch on lights—when we’re camping, for example—people tend to go to sleep shortly after dark and sleep much longer.
When we’re exposed to bright lights and screens after dusk, Harvard Medical School associate professor of medicine Steven Lockley told The Guardian,5 “our daytime physiology is triggered and our brains become more alert.” Regularly staying up after dark, he said, puts us in a state of “mini jet lag.”
What you can do about it
To manage noise:
- Use earplugs. Most earplugs will dull the noise of city traffic enough to help you get a much better night’s sleep. But be aware that they need to be cleaned or changed often so they don’t cause an ear infection. A guide to choosing and using earplugs can be found here.6
- Keep your bed away from the window. That will lessen the intensity of street noise somewhat, especially if you can also keep the window closed.
- Invest in “soundproof” windows or curtains. These aren’t actually sound-proof, but they can help quite a bit. Soundproof windows can block up to 95 percent of noise. Soundproof curtains are less effective but less costly—and can pull double-duty, blocking both light and sound.
- Try white noise—or better yet “pink noise.” A white noise machine or a fan may help soothe you to sleep and help to cover up startling street noise. There’s also such a thing as pink noise,7 a more balanced and natural-sounding cousin of white noise that appears to produce even deeper sleep.
To manage light:
- Turn off electronics well before bedtime. Electronic devices put out sunlight-mimicking blue light, which can confuse your circadian rhythm.8 This makes you more alert and can make it much harder to fall asleep.
- Get blackout shades for your bedroom. These are very effective and can block up to 100 percent of the light coming into your bedroom, no matter the time of day.
- Wear an eye mask. These come in a variety of styles9 and are generally comfortable and do a good job of blocking light. They also have the benefit of being portable.
References:
1. “Environmental noise and sleep disturbances: A threat to health?” Sleep Science, December 2014. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4608916/
2. “This Is How Your Brain ‘Hears’ Things When You’re Asleep,” by Bahar Gholipour, HuffPost, June 2016. https://www.huffpost.com/entry/how-your-brain-hears-things-asleep_n_57615cd0e4b05e4be86045fd
3. “How Noise Can Affect Your Sleep Satisfaction,” National Sleep Foundation. https://www.sleepfoundation.org/articles/how-noise-can-affect-your-sleep-satisfaction#:~:text=Noisy%20Environments%20Cause%20Restlessness,shifting%20between%20stages%20of%20sleep.
4. “Darkness Matters - How Light Affects Sleep,” ResMed. https://sleep.mysplus.com/library/category2/article1.html
5. “Urban light pollution: why we’re all living with permanent ‘mini jetlag,’ ” by Ellie Violet Bramley, The Guardian, October 2014. https://www.theguardian.com/cities/2014/oct/23/-sp-urban-light-pollution-permanent-mini-jetlag-health-unnatural-bed
6. “Is It Safe to Sleep with Earplugs?” Healthline, September 2019. https://www.healthline.com/health/sleeping-with-earplugs
7. “The Sound of ‘Pink Noise’ Improves Sleep and Memory,” by Amanda MacMillan, Time, March 2017. https://time.com/4694555/pink-noise-deep-sleep-improve-memory/
8. “Why Electronics May Stimulate You Before Bed,” National Sleep Foundation. https://www.sleepfoundation.org/articles/why-electronics-may-stimulate-you-bed#:~:text=Here's%20what%20happens%3A%20Using%20TVs,more%20difficult%20to%20fall%20asleep.
9. “10 Best Sleep Masks of 2020 for the Most Restful Sleep,” by Emma Seymour, Good Housekeeping, April 2020. https://www.goodhousekeeping.com/health/g25572070/best-sleep-masks/