A new study, published in The Lancet, states that those who live near major roadways are 7% more likely to develop dementia than those who do not.
According the study, proximity to a major roadway may also include higher instances of Parkinson’s disease and multiple sclerosis.
Researchers found that the closer a person lived to the busy road, the higher their chances were of developing dementia, which includes Alzheimer’s.
The risk level also decreases proportionately depending on how far away ones lives to the heavy traffic.
It was found that those within 50 meters (or 164 feet) of the busy road faced the greatest risk of developing the devastating disease.
However, those living 50 to 100 meters away (328) feet had their risk level drop to a 4% higher risk than the rest of the population, while 101 to 200 meters (656 feet) had their risk level drop even further to a 2% higher risk than those who did not live near a busy road.
For the study, 6.6 million people from Ontario, Canada were followed from 2001 to 2012.
Using their zip codes, researchers were able to pinpoint how close each participant lived to a major road.
They then pored through their health data to correlate their house’s proximity to a main road to diseases like dementia, Parkinson’s and multiple sclerosis.
During the time of the study, a quarter of a million of those participating were diagnosed with dementia, while significantly lower numbers of people were diagnosed with Parkinson’s or multiple sclerosis.
While there may be a connection with the latter two and heavy traffic, the researchers did not see a clear enough pattern to declare one.
While the research certainly provides interesting conclusions, the team noted that they cannot prove a cause and effect for high dementia rates and the proximity to major roads.
One theory is that heavy air pollutants from cars and trucks cause damage to the brain.
While this may be partially true, researchers on this particular project believe there is more to it and perhaps the noise level also causes issues that lead to dementia.
They also believe that other air pollutants, aside from those that cars distribute, may be part of the problem.
Those who conducted the study say that more research is needed urgently and that urban and city planners should begin to take the correlation seriously before more people are affected with dementia.