Could pollution be to blame for why dementia is killing more people and being diagnosed earlier than ever? That's the theory being floated by researchers involved in a study of patients in 21 countries from 1989 to 2010. The Smithsonian reports that while dementia is typically associated with people older than 60, the study finds that diseases such as Alzheimer's are now being regularly diagnosed in people in their late 40s. Death rates, too, are rising, particularly in the US, where American men over 75 are three times as likely and American women five times as likely to die from neurological disease than they were 20 years ago, notes the Washington Post. So what is it about modern life that's causing what researchers label a "hidden epidemic"? Lead author Colin Pritchard of Bournemouth University has a hunch.
“The environmental changes in the last 20 years have seen increases in the human environment of petro-chemicals—air transport—quadrupling of motor vehicles, insecticides and rises in background electro-magnetic-field, and so on,” he writes. Researchers admit part of the increase could be explained by better treatments for cancer and heart disease, which used to kill elderly people before dementia could. But, they argue that neither this, nor aging populations and better diagnoses, could entirely account for such a steep increase. Researchers say this is a wake-up call to make environmental changes, but not everyone is so sure. One doctor tells the London Times, which first reported on the study, that dementia is a complicated disease that could be caused by a "complex interplay" of factors. (One diet apparently cuts Alzheimer's risk by 53%.)