Noise isn't just annoying, it's a silent killer you need to avoid

Noise is defined as unwanted sound. Those who mostly live in crowded cities and towns are only too familiar with noise. This is so much so that neighbourhood associations always petition the relevant authorities to limit noise in residential areas. This is all for good reasons as noise has been dubbed as not just an annoyance, but also an unknown and silent killer.

First, where does all the noise come from? Nearly every economic activity generates some noise. What matters is the extent, measured in what is known as decibels, or simply the intensity of the noise. In urban centres, traffic is a major source of noise. Think of all the cars, buses, trucks and motorcycles on unending trips. Then there are industries, entertainment joints with loud music, and even unruly neighbours with overnight parties and constantly barking dogs. Countless daily activities are endlessly churning out intolerable noise.

The next question is how noise contributes to ill health. When sound enters your ears, it is detected by an emotional centre in the brain. Depending on the brain’s interpretation of the sound, stress hormones are released which then activate several body systems. Your heart rate goes up, and so does your blood pressure and activation of immune mechanisms that include inflammation. Over time, the risks of heart attacks, stroke, and metabolic conditions, such as diabetes and mental illnesses all rise. And all this happens even when you are deeply asleep. Eventually, the rates of death rise as well.

Back to noise levels. The louder the noise, the more irritation and negative associations with health. In decibel units (dB), a quiet library will have levels of about 40 dB. Cars and motorbikes will exceed 100 dB. Entertainment joints with uncontrolled loud music can reach higher levels. Sounds above 80dB are considered too loud, dangerous and even harmful to human hearing. For sound sleep, the recommendation is for average annual exposure not to exceed 40 dB. Long-term exposure to levels above 55dB can trigger chronic health conditions.

You, therefore, have pretty good reasons to avoid noise. In this day and age, you will not avoid noise completely. What you must do is take steps to minimise exposure to unhealthy noise. Some actions are directly in your control, such as limiting the sound levels of self-entertainment. Avoid noisy places if at all possible. Be mindful of others when participating in or directing noisy activities.

For the noises you cannot directly control, other avenues, such as noise-cancelling gadgets are at your disposal. Licensing authorities can also be lobbied to limit noise in residential areas, schools and office spaces. If you live near a busy road, your actions may be limited.

Dr Murage is a Consultant Gynecologist and Fertility Specialist.