We examine the new research investigating whether exposure to air pollution could increase the risk of dementia.
What are the claims about air pollution and dementia risk?
The idea of air pollution raising risk of dementia has been around for some time.
In recent years we’ve seen greater attention given to whether exposure to air pollution can put us at greater risk of developing dementia.
Large studies have taken place looking at whether living in an area of high air pollution might increase dementia risk.
What is 'air pollution'?
Air pollution has been a focus of several studies on cognitive impairment and dementia risk.
What does the research show?
Recent research has suggested that some of the particles we inhale from pollution can make it into our brains. It isn’t clear how these might affect the brain or whether they start or worsen dementia.
Research presented at the Alzheimer’s Association International Conference in Chicago in July 2018 suggested that exposure to air pollution could cause some areas of the outer layer of the brain – the cortex – to become thin.
Another study found the same effect on the cortex, but found that air pollution did not result in an increase in deposits of the toxic amyloid protein, which is a feature of Alzheimer’s disease. We still do not know whether air pollution is actually connected to dementia.
Were air pollution to cause dementia, we would expect more people to be diagnosed with the condition and at a younger age in cities and large towns than in rural areas – this isn’t the case. While more research is required to understand how pollution particles might affect the brain, there is currently no reason to be unduly worried about pollution as a cause of dementia.
Understanding dementia risk
What we can do is focus on reducing our risk of dementia by making positive lifestyle changes. This could include being physically active, eating a healthy diet, avoiding smoking and cutting down on alcohol.
Reducing your dementia risk
Use the Alzheimer's Society interactive tool to understand how different factors can affect your risk of dementia. Risk factors include age, genetics, lifestyle choices and health conditions.