Researchers from the Barcelona Institute for Global Health recently conducted a study, published in the Environmental International, to determine the link between long-term exposure to road traffic and obesity risk.
To do so, they examined 3,796 adults who took part in the population-based Swiss study. They recorded the participants’ weight, height, body mass index, waist circumference, and abdominal fat. They also estimated their exposure to transportation noise in decibels, a unit used to measure the intensity of a sound.
Ten decibels is the sound of normal breathing, 60 decibels is the level of an typical conversation in the office, a telephone ring is about 80 decibels, a jackhammer produces about 100 and an airplane takeoff is 120.
After analyzing the results, they found people exposed to the highest levels of traffic noise are at greater risk of being obese. In fact, a 10 decibel increase in mean noise level was associated with a 17 percent increase in obesity.
"Our study contributes additional evidence to support the hypothesis that traffic-related noise affects obesity because the results we obtained in a different population were the same as those reported by the authors of earlier studies, coauthor Maria Foraster said in a statement.
The team also evaluated exposure to noise from aircraft and railway traffic and found no apparent relationship. However, there was a link between long-term exposure to railway noise and higher risk of overweight.
A previous study from researchers of Johannes Gutenberg University in Germany found that noise is linked with oxidative stress, vascular damage, autonomic imbalance, metabolic abnormalities. They said it can also eventually lead to the development of heart disease risk factors such as hypertension and diabetes.
"In the long term, these effects could give rise to chronic physiological alterations, which would explain the proven association between persistent exposure to traffic-related noise and cardiovascular disease or the more recently discovered associations with diabetes and obesity," Foraster concluded. "Our findings suggest that reducing traffic-related noise could also be a way of combating the obesity epidemic."