Scientists find link between traffic noise and midriff bulge

Traffic noise increases the risk of getting a spare tyre, it has emerged.

Tue, 26 May, 2015 - 01:00

Evelyn Ring

Scientists have found a link between road traffic noise and a heightened risk of developing a midriff bulge — with a combination of road, rail, and aircraft noise posing the greatest risk.

Noise exposure may be a psychological stressor, increasing the production of the hormone, cortisol, thought to be responsible for depositing fat around the middle of the body.

“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,” the researchers wrote.

They suggest that noise from road, rail, or aircraft traffic may affect metabolic as well as cardiovascular functions, through sleep disturbance, altering appetite control and energy expenditure.

The researchers, whose findings are published online in the BMJ’s Occupational and Environmental Medicine, assessed how much traffic noise 5,075 people in Sweden were exposed to since 1999.

The people, living in five suburban and rural areas around Stockholm in Sweden, took part in a diabetes programme examining risk factors for the disease and how to prevent it.

Between 2002 and 2006 when they were aged between 43 and 66 they filled in a detailed questionnaire on environmental noise pollution from road traffic, trains, and planes.

The researchers found an association between road traffic noise and waist size — a change of 0.16cm for every five-decibel increase in noise exposure inroad traffic and the association was stronger in men. Exposure to road, rail and aircraft noise was associated with a larger waist. The link was strongest for aircraft noise.

The findings were not influenced by socio-economic factors, lifestyle, or exposure to ambient air pollution from local road traffic.

However, age was found to be an influential factor, with associations between central obesity and road traffic noise only found for those below the age of 60.

The researchers from the Institute of Environmental Medicine in Stockholm point out it was an observational study so no definitive conclusions could be drawn about cause and effect.

They were not able to assess levels of residential sound insulation or the locations of the participants’ bedrooms.

Meanwhile, another study published in the BMJ’s journal Gut reveals that very overweight teens may double their risk of bowel cancer in middle age.

Scientists from the Harvard School of Public Health in the US tracked the health of almost 240,000 Swedish men conscripted into the military between the ages of 16 and 20 in 1969-76.