Overview
What is it?
White noise is a type of sound that contains all frequencies at equal intensity, often described as a 'shhh' sound. It is naturally occurring and can be found in sounds like rain, ocean waves, or wind. White noise is commonly used to mask disruptive noises and create a calming environment, especially for improving sleep.
How does it work?
White noise works by masking external sounds that might otherwise disturb sleep. It creates a consistent auditory backdrop that helps drown out sudden noises, such as traffic or household sounds, which can interrupt sleep. By reducing the contrast between background noise and peak noises, it helps the brain relax and promotes a more restful sleep environment.
What are the benefits?
White noise has been shown to improve sleep quality by reducing sleep onset latency (the time it takes to fall asleep), decreasing nighttime awakenings, and increasing the arousal threshold to background noise. It is particularly helpful in noisy environments, such as urban areas or hospitals, where external sounds can disrupt sleep. Additionally, it may help synchronize circadian rhythms and improve overall sleep duration.
Effectiveness
What does the research say?
Research on white noise for improving sleep shows mixed results. Some studies suggest that white noise can significantly improve sleep quality, especially in noisy environments. For example, one study found that 80% of neonates fell asleep within five minutes when exposed to white noise, compared to only 25% in a control group . However, other studies indicate that the evidence is not strong, with only 33% of reviewed studies reporting positive outcomes . More research with objective measures is needed to confirm its effectiveness.
Side Effects
Potential hearing damage
Prolonged exposure to high volumes of white noise (above 75 dB) may lead to hearing damage over time, especially in children .
Discomfort or irritation
Some individuals may experience discomfort or irritation from the constant sound, particularly if the volume is too high or the noise is not soothing to them .
Dependency on white noise for sleep
Relying on white noise for sleep may lead to dependency, making it difficult to sleep without it in quieter environments .
Evidence
Clinical Studies & Trials
[1] Noise as a sleep aid: A systematic review.
This systematic review examines the relationship between continuous white noise and sleep. The findings are mixed, with some studies suggesting improvements in sleep quality and others indicating potential disruptions. The quality of evidence is very low, and more research is needed.
View study[2] The effects of white noise on sleep and duration in individuals living in a high noise environment in New York City.
This study tested the hypothesis that white noise improves sleep in individuals living in noisy urban environments. The results suggest that white noise can help mitigate sleep disturbances caused by environmental noise.
View study[3] White noise and sleep induction.
This study found that white noise significantly increased the likelihood of neonates falling asleep, with 80% falling asleep within five minutes compared to 25% in the control group.
View study[4] Acoustic stimulation as a promising technique to enhance slow-wave sleep in Alzheimer's disease: results of a pilot study.
This study found that acoustic stimulation, including white noise, significantly increased slow-wave sleep duration in patients with Alzheimer's disease, nearly doubling the time spent in this restorative sleep stage.
View study[5] White Noise and Its Potential Applications in Occupational Health: A Review.
This review highlights the benefits of white noise for improving sleep quality, particularly in noisy environments. It also discusses its potential applications in occupational health settings.
View study[6] Systematic review: auditory stimulation and sleep.
This systematic review evaluates the effectiveness of auditory stimulation, including white noise, for improving sleep. While some studies report positive outcomes, the overall evidence is not strong, and the risk of bias is high.
View study[7] Continuous white noise exposure during sleep and childhood development: A scoping review.
This review discusses the potential risks of continuous white noise exposure during sleep, particularly in children, including hearing damage and developmental issues.
View study