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Unpleasant noise enters your body through your ears, but it is relayed to the stress detection center in your brain.

This area, called the amygdala, triggers a cascade of reactions in your body. If the amygdala is chronically overactivated by noise, the reactions begin to produce harmful effects.

The endocrine system can overreact, causing too much cortisol, adrenaline and other chemicals to course through the body.

The sympathetic nervous system can also become hyperactivated, quickening the heart rate, raising blood pressure, and triggering the production of inflammatory cells.

Over time, these changes can lead to inflammation, hypertension and plaque buildup in arteries, increasing the risk of heart disease, heart attacks and stroke.