The impacts of noise and light pollution on our hearts

Noise and light pollution could be impacting your heart health

10 October 2023

Air pollution can have devastating impacts on the body – but it’s not the only type of pollution that could put your heart health at risk.

There is increasing evidence of the negative impacts of noise and light pollution on our hearts, meaning your neighbour’s daily leaf blowing or that extra bright streetlight outside your bedroom window may be more than just a slight annoyance.

What is noise and light pollution?

Noise pollution

Noise pollution is unwanted and excessive sounds that can negatively impact people and other organisms within that environment. Sounds are measured in decibels, with noises over 75 decibels being classed as potentially harmful.

Examples of noise pollution include:

• Transport noise e.g. cars, trucks, trains, planes
• Construction and industrial noise
• Noise from cultural and leisure activities e.g. concerts, festivals, sporting events 
• Neighbourhood noise e.g. gardening equipment, barking dogs, social gatherings

Light pollution

Light pollution is the excessive or inappropriate use of artificial lighting that impacts the naturally occurring darkness of a particular environment.

Examples of light pollution include:

• Streetlights
• Illuminated signs
• Internal lighting from office buildings
• Floodlights e.g. to light up sporting ovals
• Commercial area lighting e.g. lighting around shopping centres

What impact does noise have on the body?

When we hear a loud or disruptive noise, the body’s stress response is triggered by an area of the brain known as the amygdala, which is responsible for processing negative stimuli.

Once the amygdala sounds the alarm, this causes the hypothalamus (which acts as the link between the endocrine system and the nervous system) to activate the sympathetic nervous system, releasing hormones such as adrenaline and cortisol. 

These hormones help trigger our body’s ‘fight or flight’ response - that is, we get prepared for danger by being ready to run away or to fight - by raising our heart rates, increasing our blood pressure, and suppressing nonessential functions during short-term danger, including our immune function. 

While this stress response is useful when we need to act quickly, when it’s consistently activated over time due to stimuli such as noise, this increase in heart rate, blood pressure and inflammation can negatively impact our health. 

What does the research say about the impact of noise and light pollution on heart health?

Noise pollution

Long-term exposure to traffic and railway noise was associated with deaths from most cardiovascular diseases in a study of over four million people. These risks were seen even below the World Health Organization’s Environmental Noise guideline levels and were independent of air pollution.

Interestingly, higher levels of intermittent loud noises were also associated with heart disease – suggesting that even the occasional jarring loud noise can be harmful to our health.

The health impacts of traffic noise were also seen in a study of approximately 240,000 people over eight years, where long-term exposure was associated with an increase in hypertension (high blood pressure). This impact was amplified when noise pollution was coupled with higher air pollution.

Exposure to aircraft noise has been linked to increased cardiovascular inflammation and dysfunction in mice studies. The research found this increased immune response led to worse outcomes in mice that experienced a heart attack.

It’s not just long-term aircraft noise exposure that can impact heart health, with a UK study finding one night of airplane noise was linked to a slight increase in cardiovascular disease hospital admissions the following day.

Light pollution

Night-time light pollution can impact circadian rhythms, causing poor sleep, a cardiovascular disease risk factor.

Though light pollution is under-studied compared to noise pollution, initial studies suggest exposure to excess light may influence heart health.

In a cohort study of older adults in Hong Kong, outdoor light at a person’s residence was associated with an increased risk of hospitalisations and deaths from coronary heart disease.

A small study of 20 people found that those who spent one night exposed to light during sleep had an increased night-time heart rate and higher insulin resistance the following morning.

Further research is needed, particularly large-scale studies, to better understand how light pollution may impact heart health and the potential mechanisms behind this link.

What can you do to reduce noise and light pollution?

Noise pollution

Ways of reducing the impacts of noise pollution may include:

• Closing windows and doors in your home or office when there is excessive noise outside
• Protecting your ears by wearing earplugs or noise-cancelling headphones in noisy environments
• Using sound-absorbing material in your home, e.g. double-glazed windows, carpet, rugs, etc
• Keeping music and other sounds in your home to an appropriate level
• Creating a dedicated quiet space in your home
• Visiting prospective properties at different times throughout the day when house hunting to get a sense of what neighbourhood noises you may be dealing with
• Being a considerate neighbour by keeping noise to a minimum and advising neighbours if there’s likely to be excess noise at your property, e.g. if you’re hosting a large social gathering
• Dampening disruptive sounds like road noise with more relaxing sounds, e.g. white noise machines or nature sound apps

Light pollution

Ways of reducing the impacts of light pollution may include:

• Having effective blinds in your home to block out outside light – especially in bedrooms
• Turning off lights when not in use
• Using lighting with dimmers, timers, and motion sensors
• Choosing outdoor lighting that points towards the ground rather than upwards
• Choosing warm (yellow) lighting rather than cool (white/blue) lighting
• Putting devices like mobile phones on night mode
• Gaining an understanding of the amount of light pollution you may be exposed to using a light pollution map