Many people rely on background sound to fall asleep, ranging from ocean waves to various "noise colors" such as white, pink, or brown noise.

However, the effectiveness of these sounds is far from universal. According to Dr. John Saito from the American Academy of Sleep Medicine, any sound perceived during sleep can influence its quality, much like light or air conditions.

On the one hand, sudden or chronic environmental noises—such as traffic or airplanes—can disrupt sleep by triggering stress responses. Even when we are asleep, the brain continues to process external stimuli.

As a result, disturbances may elevate cortisol levels, increase heart rate, and interrupt restorative sleep cycles.

On the other hand, individual differences in sleep architecture play a crucial role.

Some people, known as deep sleepers, can effectively filter out noise due to brain activities like sleep spindles, while others are easily awakened by minor sounds. This variation explains why no single type of sound works for everyone.

In terms of sound types, white noise distributes frequencies evenly and may mask disruptive sounds. Brown noise emphasizes lower frequencies, producing a deeper tone, while pink noise offers a more balanced spectrum.

Although these sounds are often considered beneficial, recent studies suggest they may reduce REM sleep and potentially impair sleep quality.

Ultimately, the most suitable sleep environment depends on personal preference and individual conditions. While certain sounds may promote relaxation, others—such as loud music or television—are clearly detrimental.

In fact, experts suggest that a quiet and dark environment remains the ideal setting for optimal sleep.