POSTED: Tuesday, August 20, 2013 - 3:00am
UPDATED: Tuesday, August 20, 2013 - 3:04am
MEDICAL NEWS (CNN) — Copper, which is found in anything from drinking water to red meats, may be an environmental trigger of Alzheimer’s disease, according to a new study.
The study, published Monday in the journal Proceedings of the National Academy of Sciences, suggests copper keeps toxic proteins from leaving the brain.
It is clear that, over time, copper impairs the systems through which amyloid beta is removed from the brain, said Rashid Deane, a research professor in the University of Rochester Medical Center Department of Neurosurgery, member of the Center for Translational Neuromedicine, and lead author of the study. This causes the protein "to accumulate in the brain and form the plaques that are the hallmark of Alzheimer's disease."
Copper is usually found in drinking water that is carried by copper pipes. It is also found in shellfish, meats, nuts and many vegetables and fruits. The mineral is important for the body because it helps with the development of the nervous system, along with bone growth and hormone secretion.
Researchers looked at the effect of copper-laced drinking water on mice. They used low doses of copper over a three-month period. The dose was 10% of the maximum contaminant level set by the Environment Protection Agency.
"These are very low levels of copper, equivalent to what people would consume in a normal diet." said Deane. "We chose copper in water because it is easily absorbed in the blood."
Even with the low levels of copper, scientists found a buildup of toxic proteins in the brain. The toxic protein is called amyloid beta, which is a component of amyloid plaques that have been previously connected to Alzheimer's disease.
Research conducted using mice doesn't necessarily translate to humans, but study authors found that in both mice and human brain cells, copper exposure prohibited the removal of the harmful protein from the brain. Researchers also found that copper exposure led to a breakdown of the blood- brain barrier, making it easier for copper to get into the brain as well.
"Copper is an essential metal, and it is clear that these effects are due to exposure over a long period of time," said Deane. "The key will be striking the right balance between too little and too much copper consumption. Right now we cannot say what the right level will be, but diet may ultimately play an important role in regulating this process."
Deane says people should know more about copper and its effects. "Because of what I do, I believe in preventive medicine and practices," notes Deane. "Copper is essential. But maybe, just maybe, if we are finding that copper is creating a problem in the brain, we should back off on supplements, look at labels on foods and know how much copper we are putting in our bodies. We don't need to overdo it."