There are many noises around us, such as harsh construction sounds, noisy crowds, and more. We’ve all experienced being disturbed by noise, finding it difficult to concentrate and feeling irritable. Sometimes, excessive noise can even cause dizziness and ringing in the ears. However, the harm caused by noise goes far beyond these effects. In the World Health Organization’s report “Burden of Disease from Noise Pollution,” noise is listed as the second largest killer of public health after air pollution. In this edition of the health headline, let’s discuss in detail the impact of noise on health.
Firstly, noise has an unexpected harm: it can contribute to weight gain. A study conducted by Karolinska University Hospital in Sweden found that residents exposed to long-term noise are more likely to develop abdominal obesity and have a 25% increased risk of increased waist circumference compared to those living in quiet environments. For every 5-decibel increase in noise level, the residents’ waist-to-hip ratio increases by approximately 0.16 units, and this phenomenon is more pronounced in men. The researchers point out that, on the one hand, noise affects the secretion of hormones such as cortisol, adrenaline, and noradrenaline in the body, which affects fat breakdown. On the other hand, noise induces stress, which then affects our appetite control.
Secondly, noise can also harm the cardiovascular system. Studies have found that individuals who are exposed to severe traffic noise, such as from airplanes or trains, for a prolonged period have an increased risk of developing hypertension and heart disease. A five-year investigation conducted by the University of Kentucky College of Public Health also discovered a significantly elevated risk of coronary heart disease in individuals exposed to long-term noise.
Furthermore, noise can potentially damage learning abilities, visual and auditory functions, and the cerebral cortex. The “European Night Noise Guidelines” state that noise at around 55 decibels negatively affects children’s learning, noise at around 80 decibels increases the risk of deafness by 50%, and noise at around 90 decibels reduces the retina’s sensitivity to light. If the noise exceeds 115 decibels, it can lead to functional decline in the cerebral cortex.
After hearing this, you may think that staying away from noisy places and spending time at home will help avoid noise interference. However, there are still many “invisible” noises lurking in our homes, such as the sound of air conditioning and refrigerators running, computer fan noise, and honking from the street. Initially, we may find these sounds a bit bothersome, but over time, we tend to ignore them. However, these “invisible” noises still impact our health. To mitigate the impact of noise on our health, we can start by addressing the three elements of noise propagation: “sound source, transmission path, and receiver.” Correspondingly, there are three methods: weakening the sound source, cutting off the transmission path, and controlling the receiver.
To weaken the sound source, it is recommended to avoid overly noisy environments when going out and choose appliances with lower noise levels at home. Regularly clean or repair appliances that have become noisy due to age. To cut off the transmission path, we can place large plants with dense foliage near windows to reduce noise penetration. If feasible, installing soundproof glass can also be an option. In terms of controlling the receiver, when the environment is noisy, wearing earplugs or using noise-canceling headphones can effectively reduce noise. It is important to note that the volume of headphones should not exceed 60% of the maximum volume, and continuous headphone use should ideally not exceed 60 minutes.