It's out there and you can't escape it. Much like monsters from the horror movies of your childhood, noise is something that seems to be lurking around every corner and yet is invisible. And "noise" isn't simply the racket your neighbors make—it's the everyday hum of our existence. The drone of traffic, buzz of our electronics, and whoosh of overhead aircraft may be things we don't notice, but they’re always around us and are negatively affecting our health.

A German study found that noise levels above 60 decibels throughout the day led to increased cardiac risk— 60-70 dB is about the equivalent of listening to loud laughter. Going up the scale, 120 dB is similar to listening to thunder or being next to loud speakers at a concert. "Exposure to 85 dB over time can add up to hearing loss and the louder the noise, the less time required for hearing loss to occur," says Nancy Nadler, executive director of the Center for Hearing and Communication in New York City.

"Although relative risks may be small compared with other risk factors such as smoking, public health relevance is given by the large number of noise-exposed people," says Wolfgang Babisch, MSc, PhD, of Germany’s Federal Environment Agency. Unless you live underneath a (soundproof) rock, you're in the population of the noise-exposed.

Why "Normal" Noise Affects Your Health "When you’re in a noisy restaurant, those levels might not be able to damage your hearing but you'll have to strain and speak louder. You're working so much harder and it's creating tension," Nadler says. The main pathways for low-level noise (less than 60 dB) to affect cardiac and endocrine health is through the buildup of stress and disruption of sleep.

When the auditory nerves in your ears are constantly reacting to dBs, your nervous system (which affects your blood pressure and heart rate) and endocrine system (which regulates the release of stress hormones) never get a break. All nerves feed into the nervous system, and if you're constantly stimulated, your cardiac system is consistently in a situation of stress that, over time, can lead to cardiovascular risk factors like high blood pressure. "Conscious and non-conscious perception of noise can cause physiological stress reactions in the nervous system. Persistent noise stress [can disrupt your metabolism]," Babisch says.

One of the biggest problems with noise is sleep disturbance. Constant low-level noise (40-45 dB) causes your auditory nerves to continuously stimulate your brain and cardiovascular system— without even waking you up. That work can give you a restless night's sleep, even if you didn't notice. In tests, "even subjects that report that they were not disturbed by the noise during sleep show physiological reactions," Babisch says.

Protect Yourself While you are at greater risk for noise-related health problems in urban areas, individuals have varying degrees of susceptibility. "People in exposed areas are at a higher risk, but not everybody gets [affected]," Babisch says. For some, noise just isn't a problem.

It would be ideal if there were public policy moves to reduce noise pollution, especially from road traffic, which "is the most widely distributed noise source in the environment," Babisch says. In the meanwhile, take these small steps at home to lessen your risk:

• Escape: Move your bedroom to a quieter side of the house or room if possible, use earplugs, and close the windows when you are feeling particularly ill-rested.
• Sleep: Having trouble getting to sleep? Earplugs, heavy curtains, and closed windows are a great place to start when trying to reduce noise in the bedroom.
• Join an Action Group: An anti-noise group is a great resource for more ideas to lower the volume in your community.
• Moderate Your Behavior: Even if you aren’t affected by noise, consider your neighbors and try to reduce the noise you make. "Neighborhood noise comes often second in the ranking of annoying noise sources in large community surveys, after road traffic," Babisch says.