Air pollution, a lack of vitamin D and pesticides ‘increase YOUR risk of dementia’
Experts have listed environmental factors which may contribute to the disease
AIR pollution, impure water and vitamin D deficiency may all cause dementia, a study suggests.
Experts have included them on a shortlist of environmental factors that may increase the risk of developing the degenerative brain disease.
Dementia is known to be associated with high blood pressure in mid-life, smoking, diabetes, obesity, depression and low educational attainment.
But these genetic, medical and lifestyle factors leave around a third of dementia risk unexplained.
Now researchers from the University of Edinburgh have reviewed dozens of previous studies to identify whether other issues are at play.
They found a lack of vitamin D – produced by the body through exposure to sunlight – and exposure to air pollution were implicated.
Occupational exposure to some types of pesticide was also identified.
Excessive levels of minerals found in drinking water may be linked to the disease, the research published in the journal BMC Geriatrics suggested – but the evidence here was mixed.
Dementia is a major global public health crisis that is expected to grow as people live longer.
Almost 47 million people live with dementia worldwide and this is predicted to increase to more than 131 million by 2050.
Estimates indicate the disease costs the UK more than £26billion a year and worldwide dementia care costs exceed the market value of Google or Apple.
There is a growing agreement among doctors that a significant proportion of cases could be prevented or delayed by addressing environmental factors linked to the disease.
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The team behind the latest research says future studies should focus on the short list of environmental risk factors flagged up in their study.
Dr Tom Russ, from the university, said: “Our ultimate goal is to prevent or delay the onset of dementia.
“Environmental risk factors are an important new area to consider here, particularly since we might be able to do something about them.
“We found that the evidence is particularly strong for air pollution and vitamin D deficiency.
“But we really need more research to find out whether these factors are actually causing dementia and how, and if so, what we can do to prevent this.”
Dr Doug Brown, Director of Research and Development at the Alzheimer’s Society, said: “Dementia is incredibly complex and we are yet to fully piece together how genes, lifestyle and environmental factors interact to determine a person’s risk of developing the condition.”
Prof Tom Dening, Professor of Dementia Research at the University of Nottingham, said: “What is difficult is to tell whether the environmental exposures are themselves contributing to dementia or whether they are in fact acting as proxies for some underlying variable.”
Dr Rosa Sancho, Head of Research at Alzheimer’s Research UK, said: “Dementia is one of the most feared conditions and public interest in what might influence dementia risk is understandably high.
“This new analysis of existing studies has identified a shortlist of environmental factors that could be associated with dementia risk, but strong evidence behind these factors is still lacking.
“It is important to remember that association does not necessarily indicate causality, and that diseases like Alzheimer’s have a complex mix of risk factors including age and genetics.”