Oxford researchers discovered the part of your commute that is causing weight gain

Anyone who has ever lived close to a busy road or highway knows just how annoying the constant sounds of the road can become. Car horns, revved up engines, and backfiring exhausts aren’t exactly a comforting lullaby in the evening, nor are they a gentle morning alarm clock.

Most people, though, don’t let a little traffic noise stop them from taking advantage of a great apartment or experiencing city living for the first time. After all, what harm can a few car horns really do? Surprisingly, a new study finds that prolonged exposure to traffic noise actually does carry a pretty significant potential health complication. 

Researchers from Oxford University and the University of Leicester have discovered a connection between traffic noise and obesity. They say that long-term exposure to traffic noise is associated with both an increase in BMI and waist circumference. Suddenly, it makes much more sense why that great apartment right next to the highway has such low rent.

“While modest, the data revealed an association between those living in high traffic-noise areas and obesity, at around a 2% increase in obesity prevalence for every 10dB of added noise,” says lead study author Dr. Samuel Yutong Cai, a senior epidemiologist at the University of Oxford, in a release. “The association persisted even when we accounted for a wide range of lifestyle factors, such as smoking, alcohol use, physical activity and diet, as well as when taking into account socio-economic status of both individuals and the overall area. Air pollution was also accounted for, especially those related to traffic.”

Does this mean that car horns and traffic noise cause people to gain weight? The research team says they can’t establish a direct causal relationship between obesity and traffic noise but speculate there may be more of a domino effect at play here. For instance, imagine being woken up every night at 2 A.M. by car alarms. After a few days, that’s going to take a toll on your psychological state. Naturally, you start feeling more stressed because you can’t sleep at night. Well, stress has long been linked to weight gain.

“It is well-known that unwanted noise can affect quality of life and disturb sleep,” explains study co-author Professor Anna Hansell, Director of the University of Leicester’s Centre for Environmental Health and Sustainability. “Recent studies have raised concerns that it also may influence general health, with some studies suggesting links to heart attacks and diabetes. Road traffic noise may increase stress levels, which can result in putting on weight, especially around the waist.”

For this research, the study’s authors analyzed data on over 500,000 people. Those subjects were all residents of either the United Kingdom, the Netherlands, or Norway. Interestingly, there was no association noted between obesity and traffic noise among Dutch participants. The Norweigan and U.K. participants, however, did display such a connection.

“As we emerge and recover from COVID-19, we would encourage the government to look at policies that could manage traffic better and make our public spaces safer, cleaner and quieter,” Dr. Cai concludes. “Air pollution is already a well-known health risk, but we now have increasing evidence that traffic noise is an equally important public health problem. The UK should take this opportunity to think about how we can, as a society, re-organize cities and communities to support our health and reap better health outcomes across the whole population.”

Moving away from a busy street isn’t going to magically help anyone lose weight or avoid obesity all on its own. Proper diet and exercise are, of course, the pillars of any weight loss project. Still, these findings may be at least worth considering while on the lookout for a new home, apartment, or general area to live in.

Moreover, this study may prove very useful on a city planning level. If future highways and streets are designed to limit traffic noise pollution, it could help reduce obesity rates across larger regions.

The full study can be found here, published in Environmental Research.