YOUR BODY ON NOISE
When you live and work in loud places, your body goes on higher alert. “Noise exposure can cause physiological stress and changes in the nervous and hormonal systems,” Neitzel says. “These changes can trigger the fight-or-flight response, which over time can be harmful to various systems.” And it’s another way that poverty is damaging to society: Lower-income neighborhoods tend to be considerably louder than more affluent neighborhoods, with lasting effects on children living there. For everyone, here’s how noise pollution puts us at risk:
1. Chronic noise exposure is associated with learning challenges in kids and faster cognitive decline in older adults, research from Germany and the University of California, Los Angeles suggests. Plus, people who live in noisy areas, like near an airport or highway, have twice the rate of depression and anxiety as people in quiet areas, according to a study in Plos One. And exposure to noise at just 50 decibels can bring on headaches, a study from the Royal Melbourne Institute of Technology in Australia suggests. FYI, a quiet library is 30 to 40 decibels, and a vacuum is 60 to 80 db.
2. Loud noises enter your ear as sound waves, then travel down the ear canal into the inner ear. The fluid-filled cochlea is lined with tiny hair cells that send electric signals to your brain to interpret sound. Loud noise can permanently damage these hair cells, shuttering communication
to your brain, according to the American Speechlanguage-hearing Association.
3. The odds of having a heart attack increase by 12 percent for every 10-decibel increase in traffic noise, and high levels of noise can lead to an irregular heartbeat, according to German and Danish researchers. More noise also equals higher blood pressure. Research shows for every 10-decibel increase in nighttime noise from local airports, hypertension risk can rise by 14 percent.
4. Traffic noise also appears to be a contributing factor to obesity. Researchers in Spain and Switzerland studied data collected from 3,796 people and found a 17 percent increase in obesity rates for every 10-decibel increase in traffic noise level. A possible reason: hormonal and nervous system changes due to chronic noise exposure.