Researchers believe that the stress of traffic din may raise stress levels to the point where the body starts laying down more fat because it thinks it is heading for a time for crisis, when food may be scarce.
Normal traffic noise is around 45 decibels, but for every five decibels above that, the average homeowner gains an extra 0.2cm on the waist measurement.
London’s Tottenham Court Road regularly records noise of up to 80 decibels meaning residents could expect to be on average 1.4 cm larger waistlines than if they lived in a quieter location.
And noise levels around Buckingham Palace exceed 75 decibels, suggesting even the Queen may be affected by the problem.
Living under a flight path combined with a road and railway was also found to double the risk of obesity.
“Traffic noise is a common and increasing environmental exposure, primarily due to ongoing urbanisation and growth of the transport sector,” said lead author Dr Andrei Pyko, Karolinska Institute in Sweden
“Road traffic is the dominating source, followed by railway and aircraft noise. Health effects related to traffic noise are widespread and span from annoyance, sleep disturbances and changes in stress hormone levels to adverse effects on the cardiovascular system.
“Our results suggested associations with waist circumference primarily in the age group below 60 years.”
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The results suggest that people who are trying to lose weight should consider living in less urbanised environments.
And the findings are particularly worrying because obesity around the waist is one of the most harmful types of fat, and has been linked to diseases like diabetes.
The researchers assessed how much road traffic, rail, and aircraft noise 5075 people between 43 and 66 living in five suburban and rural areas around Stockholm, Sweden, had been exposed to since 1999.
They then completed a detailed questionnaire covering lifestyle, current state of health, levels of psychological distress, insomnia and job strain. They were also asked about environmental noise pollution from road traffic, trains, and planes.
The study found that there was a 0.21 cm increase for every additional 5 decibel increase in noise level. Living under a flight path doubled the rate of obesity.
In Britain, 25 per cent of adults are obese — 12 million people — compared with fewer than 3 per cent in the Seventies. The proportion is predicted to grow to one in three by 2030.
A recent study found that for every 10 decibel increase in road noise, the risk of stroke among over 65s increases by more than a quarter. Researchers at the Institute of Cancer Epidemiology in Copenhagen believe one in five strokes in urban areas could be due to living in noisy homes.
Researchers at Imperial College also found that hospital admissions for stroke, heart and circulatory disease are higher in areas with high levels of aircraft noise.
Dr Anna Hansell, at the Centre for Environment and Health, Imperial College London, said: “While interesting, this is one of the first studies to look at the link between waist size and traffic noise, so it’s definitely too soon to be able to blame your increasing waist-line on traffic noise!
“Also, the size of the reported associations with traffic noise are small. Eating a sensible diet and taking regular exercise remains the best way to help prevent a midriff bulge.
“A number of recently published studies have found associations between transport noise and high blood pressure, heart disease and stroke.
The research was published in the BMJ journal Occupational & Environmental Medicine.
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Speculation from Swedish research that stress from aircraft noise could raise risk of obesity
Millions of urban Europeans are exposed to aviation noise that contributes to stress, high blood pressure and even weight gain, say health specialists who want stronger measures to make flying quieter. While plane engines have become slightly less noisy over the past 3 decades, there are considerably more flights and also demand for bigger passenger planes – which make more noise than smaller ones. As well as the effects of exposure to noise being linked to heart and blood pressure problems, and slower learning in children in some circumstances, there is now concern about an increase in obesity. Medical researchers at the Karolinska Institutet in Stockholm have added weight gain to the potential impact of noise on public health. In a study of people living near the Swedish capital’s Arlanda Airport, the research team found that prolonged exposure to aircraft noise caused a “statistically significant” increase in waist sizes. They found a noise level raised by 5 decibels correlated with an increase in waist size of 1.5 cm. The mechanism for this may be that stress from sleep disturbance and annoyance could increase production of cortisol, leading to increased appetite.
Living near a busy road or airport can give you a pot belly claim scientists in Sweden
Scientists in Sweden claim to have discovered link between noise levels from traffic, trains and aircraft and bulging waistline
People who live near noisy traffic face a bigger risk of developing a pot belly, a study shows.
And those whose homes are near railway lines, flight paths and busy roads are the most likely to acquire a spare tyre.
Central obesity – too much fat around your waist – is said to be one of the most harmful types of fat deposition around the body.
It happens when excessive fat around the stomach and abdomen has built up to the extent that it is likely to have a negative impact on your health.
People with pot bellies face an increased risk of a number of conditions including Type 2 diabetes and heart disease.
Scientists did not find a link between traffic noise and your overall BMI, according to research published in Occupational & Environmental Medicine.
But they found that noise exposure may be an “important physiological stressor” and bump up the production of cortisol.
And high levels of this hormone are thought to have a key role in fat deposition around the middle of the body.
Prof Goran Pershagen, of the Karolinska Institutet at the Institute of Environmental Medicine, in Stockholm, Sweden, said: “This may explain why the effects of noise were mainly seen for markers of central obesity, such as waist circumference and waist-hip ratio, rather than for generalised obesity, measured by BMI.”
Traffic noise from any or all of the three sources may also affect metabolic as well as cardiovascular functions, through sleep disturbance, the study suggests, altering appetite control and energy expenditure.
The researchers assessed how much road traffic, rail, and aircraft noise 5,000 people living in five suburban and rural areas around Stockholm, Sweden, had been exposed to since 1999.
They did this, by using official figures on road and rail traffic noise levels and flow. The comprehensive study included information on ground surfaces, building heights, speed limits and noise barriers from the five areas.
They also used national data on aircraft noise from Stockholm’s main airport, Arlanda.
Between 2002 and 2006, when they were aged between 43 and 66, the participants completed a detailed questionnaire covering lifestyle, current state of health, levels of psychological distress, insomnia and job strain.
They were also asked about environmental noise pollution from road traffic, trains, and planes.
Hounslow ChronicleAeroplanes landing at Heathrow Airport
And they underwent medical tests, which included blood pressure and a test for diabetes, as well as measures of central body fat (waist and hips and the waist:hip ratio), and overall obesity (weight and height to define the body mass index or BMI).
The researchers calculated that well over half (62%) had been regularly exposed to road traffic noise of at least 45 decibels (dB) while one in 20 had been exposed to similar levels of noise from trains. More than one in five had been exposed to aircraft noise of more than 45 dB.
Just over half (54%) had been exposed to one source of traffic noise, 15% to two sources and 2% to all three. Around a third (30%) had been exposed to levels below 45 dB, which were not considered to be harmful.
The scientists found no link between road traffic noise and BMI. But there was a link between road traffic noise and waist size, with a 0.21cm increase for every additional 5 dB increase in exposure.
A larger waist was significantly associated with exposure to any of the three sources of noise, but the link was strongest for aircraft noise.
And the more sources of noise pollution a person was exposed to at the same time, the greater their risk of a pot belly seemed to be.
The heightened risk of a larger waist rose from 25% among those exposed to only one source to almost double for those exposed to all three sources at the sane time.
The scientists said their findings were not influenced by socioeconomic factors, lifestyle, or exposure to air pollution from the traffic.
But they did find the link link between a spare tyre and road traffic noise only in those aged under 60.
Commenting on the study, Dr Anna Hansell, of Imperial College London, said: “While interesting, this is one of the first studies to look at the link between waist size and traffic noise, so it’s definitely too soon to be able to blame your increasing waist-line on traffic noise.
“The study needs to be replicated in other areas and in other study populations to confirm the findings. Also, the size of the reported associations with traffic noise are small. Eating a sensible diet and taking regular exercise remains the best way to help prevent a midriff bulge.”