Too Loud for Your Heart

The world we live in has become a very noisy place. Noise is our constant companion – from the honking of cars and buses, to the chatter of neighbours and pets, and especially the nagging buzz of our gadgets; we are enveloped in a never-ending racket. This bothersome uproar isn’t just about sound. This barrage of discord disrupts our peace and tranquillity; it affects our daily lives and, unsurprisingly, impacts both our physical and mental health.

Noise not only interferes with interpersonal communication, but also disturbs our sleep and causes annoyance. Furthermore, long-term exposure to significant noise levels has been shown to negatively impact our health and well-being, even when the noise level is what we experience in our everyday lives. The World Health Organization (WHO) estimates that in western Europe, one of the most urbanised areas in the world, noise causes cognitive impairment in children, disrupting 903,000 life-years due to noise-induced sleep disturbance and 22,000 life-years due to tinnitus (ringing in the ears). The WHO also noted that noise causes heart diseases.

Impact of noise on the heart

Exposure to noise affects multiple organs and body systems. When we hear noise, the body goes on high alert, which causes a flood of stress hormones. These hormonal responses include the activation of the sympathetic responses (a.k.a. fight–flight reactions) as well as the release of corticosteroid hormones (a.k.a. defeat reaction). These hormones can cause an increase in blood pressure and heart rate. It has been found that for every 10 dB increase in noise level, the blood pressure increases by 0.84/0.44 mmHg. Frequent exposure to traffic noise, which ranges from 70 to 80 dB, may increase blood pressure by almost 7/4 mmHg.

Even if the noise is not loud, it disturbs our concentration, relaxation and sleep, triggering hormonal responses that may disrupt the level of blood cholesterol, blood sugar, magnesium and calcium. These factors increase the risk of heart diseases, including heart attack, in people with prolonged noise exposure. For example, individuals who are frequently exposed to railway noise are at an increased risk of heart diseases by 55%.

Noise-disturbed sleep and its effects on the heart

Sleep is important because it allows the body to slow down, to recuperate from a stressful day, and prepare for the new day. In contrast, disturbed sleep causes several hormonal changes. It impairs insulin secretion and decreases insulin sensitivity; both of these could lead to an increase in blood sugar levels. Appetite-regulating hormones also become dysregulated, leading to more intense hunger the next day; this in turn could lead to overeating and contribute to obesity and high blood cholesterol. Therefore, it is no surprise that noise-disturbed sleep has been associated with obesity and diabetes, both of which are risk factors that aggravate heart diseases.

Many people have reported that they can be accustomed to noise, and are able to sleep despite the noise. However, habituation to noise is not complete and the body response persists, albeit at a lower level. Therefore, quiet sleep remains better than sleep that is regularly enveloped by noise.

Give your heart peace and quiet

Scientific literature shows that noise is not only a nuisance that disturbs sleep, but also a contributor to the development of heart diseases and its risk factors, such as hypertension and diabetes. Noise-induced disturbance to sleep may lead to adverse health effects. Therefore, measures should be implemented at national and community levels to reduce noise exposure.

There are many ways you could reduce the level of noise you are exposed to:

Turn off appliances at home and in the office
Switch off electrical appliances such as the TV and radio when they are not in use. You will save electricity and create a quieter environment. If you can’t, or do not want to turn these appliances off, at least turn the volume down.

Isolate noise
Close the doors to noisy rooms, such as those with running dishwashers or washing machine in use. You may also close your room door if the rest of the house is noisy. Keep your appliances well-maintained to prevent them from running noisily.

Plant trees
Foliage are good sound absorbents.

Use earplugs
Earplugs or earmuffs can muffle loud noises to a tolerable level. You may use these for better sleep too.

Stay away form noisy areas
Where possible, avoid places with noisy machinery or places near airports, roads and railways.

Minimise noise creation
Instead of using your device’s speaker, use headphones or an earpiece. When you use headphones, set the bass control at a low level. If you play a musical instrument, avoid practising early in the morning or late at night. Where possible, avoid noisy renovation work. Avoid yelling and engaging in noisy activities. If you are a pet owner, tend to their needs well to prevent them from making noise.

With these simple measures, you can foster a quieter environment for you and your neighbourhood, and for a healthy peaceful heart.

Article is contributed by Clinical A/Prof Jack Tan, Honorary Secretary of the Singapore Heart Foundation. He is also the Deputy Chief Executive Officer and Senior Consultant at the National Heart Centre Singapore.