The Sleep Problem That We Often Miss

This educational article is kindly sponsored by Otifleks, who’ve asked us to write an article about sleep disruption.

We’ve talked a lot about healthy sleep at 10almonds over the years, including about how there are many factors more important than just duration. Which is important, as a lot of people focus on duration to the exclusion of other factors!

See, for example: The 6 Dimensions Of Sleep (And Why They Matter)

And, for that matter: How Regularity Of Sleep Can Be Even More Important Than Duration

But what’s this about a problem that we often miss?

The forgotten noise factor

Everyone knows that noise disturbance is not good for sleep, but the issue here is what form noise disturbance took:

• If noise has kept you awake all night, then sure, you’ll remember that and know it was a problem.
• If it was so loud and sudden that you often awoke with a start, then yes, again, you’ll remember that and know it was a problem.
• If, however, the noise merely caused low-level disruptions to your sleep throughout the night, then you’ll probably not remember it upon awakening in the morning, even though during the night you slightly awoke many times, and were unable to enter a deeply restful state.

The former two examples are big problems, but they’re big problems that anyone subject to them will know about and try to correct.

The latter example, however, can end up being a big problem that goes unaddressed, because such a person may have no idea the noise is what is causing them to not feel well-rested in the morning, since they have no memory of it causing any issues.

With regard to the harm caused, let’s consider some studies:

For the broadest overview, here’s a very large systematic review of 68 studies, that concluded:

❝Environmental noise, particularly traffic noise, significantly increases the risk of sleep disturbances. Type-specific effects were observed, and a dose–response relationship was also identified. These findings support the need for further reductions in nighttime traffic noise exposure and strengthened residential noise control to promote population sleep health.❞

Read in full: Environmental Noise Exposure and the Risk of Sleep Disturbance: A Systematic Review and Meta-Analysis

But what of how to remedy that, aside from “hope the world gets less noisy out there”?

Another recent study concluded:

❝Urban noise pollution is significantly associated with increased prevalence of sleep disorders and neurological symptoms. Individuals exposed to high noise levels experienced poorer sleep quality and more frequent headaches, dizziness and irritability. Thus, we show the urgent need for urban noise regulation and personal mitigation strategies to protect neurological and sleep health.❞

Read in full: Impact of urban noise pollution on sleep disorders and neurological symptoms

What are the best “personal mitigation strategies”?

There are two main obvious tries:

• White/pink noise to drown out the noise that is causing disturbance, with a noise that’s less disturbing
• Earplugs, to reduce all external noise stimuli

White/pink noise can be beneficial in some ways, and we’ve written about that here: White Noise vs Pink Noise

However, there may be trade-offs also, per this study that found:

❝Compared to a noise-free control night, EN reduced N3 deep sleep (p < .0001) while PN reduced REM sleep (p < .001).

Adding PN to EN worsened sleep structure, despite minor dose-dependent improvements of EN-induced sleep fragmentation and N3 sleep increases.

Earplugs mitigated nearly all EN effects on sleep but started failing at the highest EN level (65 dBA). Morning cognition, cardiovascular measures, and hearing were not affected by nighttime noise, but subjective assessments of sleep, alertness and mood were significantly worse after EN and PN exposure.❞

• EN = environmental noise
• PN = pink noise

Based on these results, the researchers concluded:

❝In contrast to PN, earplugs proved efficacious in mitigating the effects of EN on sleep. Considering the importance of REM sleep for memory, emotion regulation, and neurodevelopment, the negative effects of PN on REM sleep caution against the widespread and indiscriminate use of broadband noise (BN). Additional research on optimal BN color/level and long-term use is needed, especially in vulnerable populations.❞

Source: Efficacy of pink noise and earplugs for mitigating the effects of intermittent environmental noise exposure on sleep

So, earplugs seem indeed to be the way to go!

Disclosure: as we mentioned up top, this article was sponsored by Otifleks, a company that just happens to sell earplugs, which you can check out or not; this is an educational article and not an ad. The article was written by your usual 10almonds writing team, with our usual attention to objectively looking at the science and saying what it says, making only well-evidenced claims. In short, sponsors can ask us to write an article, but we will only write what the science says.

Indeed, this writer has alienated several sponsors before now by refusing to make claims that were untrue and/or not backed by evidence!