The paramount mantra in real estate is “Location, Location, Location.” Location impacts home values, proximity to shopping and recreational activities, what schools are available and, surprisingly, one’s waistline. A new study shows the impact of location – particularly proximity to traffic noise from cars or planes – can lead residents to pack on inches and possibly lead to obesity.
People who live closer to a major road with lots of traffic noise, near a railroad or in a airport flight path may not realize that their chronic exposure to noise adds to their stress level. It turns out that the noise also adds to their waist size. Those who regularly hear noise from more than one traffic type have an even greater risk for a burgeoning middle (also known as central obesity.)
A study involving over 5,000 individuals for a four-year period suggests “that traffic noise exposure can increase the risk of central obesity,” according to research just issued in the Occupational & Environmental Medicine, a British medical journal. A group of researchers from Sweden and Norway analyzed the traffic noise levels by more than 5,000 women and men living in Stockholm regularly endured between 2002 and 2006. They also measured the participants’ waist sizes, body mass index (BMI) and their waist to hip ratios.
The analysis found that almost two-thirds of the residents had been regularly exposed to automotive traffic noise at least 45 decibels (dB). One in 20 experienced similar levels of noise from trains. Aircraft noise above 45 dB affected more than 1,100 of the residents.
Interestingly, the researchers found no link between the noise from road traffic and the people’s BMIs. However, there was a definite correlation between the levels of road traffic noise and their waist sizes. For each additional 5 dB they regularly experienced over the 45 dB level, there was an average of 0.21 cm increase around their middles. The waist sizes increased 0.46cm and 0.99cm for each additional 5 dB in noise from trains and planes respectively. The risk of a wider waist doubled for those who heard all three types of traffic noise, according to the analysis, which may have shown a cumulative effect.
While this was an observational study so conclusions about cause and effect are not there. Other reasons may exist, but the researchers believe the chronic exposure to noise is stressful and affects, which can interfere with a person’s metabolism and hormones. They theorized that the constant exposure to traffic sounds lead to increased production of the hormone cortisol, which can stimulate more fat to accumulate around the middle forming the classic pot belly. This could provide an explanation as to why the noise effects were seen in what the scientists called “markers of central obesity” like circumference around the waste and the waist-hip ratio; this differs from markers for generalized obesity, which is typically measured by their BMI, they indicated in the journal article. Additionally, being disturbed at night is known to alter appetite control and other factors affecting weight and energy.
Additional research is needed both in other geographic areas and looking into other mitigating factors, such as socioeconomic ones. However, the data showing a connection between traffic noise and obesity can lead one to add another factor to evaluating location when looking for a place to live. Being near a major road may be good for a commuter, but those looking into a residence should consider what it would be like at various times of day.
By Dyanne Weiss
Medical Xpress: Road Traffic Noise Linked To Heightened Risk Of Mid-Riff Bulge
The Telegraph: Why living on a main road could be making you fatter
Occupational & Environmental Medicine: Exposure To Traffic Noise And Markers Of Obesity