On Aug. 27, 1883, the loudest Earth-produced noise in recorded history was emitted when a volcano erupted on Krakatoa, an Indonesian island.
The sound could be heard nearly 3,000 miles away, and within 40 miles of the explosion, people's eardrums were shattered.
Clearly, loud noise (above 60 decibels, the volume of a normal conversation) is dangerous — and it doesn't have to be Krakatoa-strong to trigger health problems. Exposure to elevated decibels can:
• Erode your hearing.
• Interfere with sleep, disrupting your endocrine, metabolic, and immune systems.
• Damage your cardiovascular system, increasing your risk of high blood pressure, stroke, heart attack, and heart failure.
Now, a review in the Journal of the American College of Cardiology provides insight into why the noise-heart damage links exist.
Loud noises cause stress, and chronic exposure to stress hormones boosts blood pressure and damages blood vessels.
Plus, one study found that blood vessels' so-called calcification burden increases by almost 4 percent with every five-decibel increase in nighttime traffic noise — upping the risk of atherosclerosis and arterial stiffening.
Loud, persistent noise also affects the autonomic nervous system that regulates organ system functions. Maybe excessive noise all over the country is why we have so much heart disease.
So, if you live in a noisy environment:
• At night, use sound-dampening earplugs.
• Install sound-blocking shades and drapes.
• -Rely on noise-canceling headphones (not while crossing the street!).
• Turn down your earbuds. Canceling out exterior sound with music piped directly into your eardrum doesn't help keep you calm or healthy.