May Play a Role in Alzheimer's
How much copper you take in could
worsen your risk of the brain-destroying disease Alzheimer's,
U.S. researchers said on Monday.
Their studies have only been done
in rabbits so far but may raise important questions about how
much copper is allowed into the water supply.
Rabbits that drank distilled water
did not develop an animal version of Alzheimer's disease, but
when ordinary tap water containing copper was given to them, they
did, said Dr. Larry Sparks of Sun Health Research Institute in
Sun City, Arizona, who led the study.
"Copper is an essential nutrient
but has also been implicated as an important factor in Alzheimer's
disease," Sparks and Bernard Schreurs of West Virginia University
wrote in their study, published in the Proceedings of the National
Academy of Sciences.
"This is something we need to investigate,"
Sparks said in a telephone interview.
The U.S. Environmental Protection
Agency has a maximum contaminant level goal for copper in drinking
water of 1.3 parts per million.
Levels in the rabbits' drinking
water were well below that. "We are working at one-tenth that,"
Sparks said his work was done in
a rabbit model of Alzheimer's. The rabbits develop symptoms and
physical signs of Alzheimer's when fed a high-cholesterol diet.
COPPER CAUSES PROTEIN BUILDUP
But he believes that copper somehow
interferes with the body's ability to clear out the amyloid-beta
protein that is an important component of the senile plaques that
clog up the brain of an Alzheimer's patient.
"If there is no copper in the water
then the amyloid beta is shuttled to the blood for clearance,"
Alzheimer's affects about 4 million
Americans and 15 million people worldwide. It is always fatal
and there is no cure, although some treatments can help for a
Symptoms start with mild memory
loss, but patients become senile and helpless. After death, their
brains are seen to be clogged up with senile plaques and tangles
of nerve cells.
Genetic as well as environmental
causes seem to be to blame and the precise culprits are hotly
Sparks has been working with rabbit
models of Alzheimer's for years. "Every time I ever fed a bunny
cholesterol, I got Alzheimer's pathology," he said.
That is, until he moved to the
Sun City lab.
"I said, 'Something is wrong. I
go down into the vivarium (where lab animals are kept) and the
first thing I see is the wall being lined with big blue bottles."'
It turns out the rabbits there
were given distilled water, while all the other research animals
Sparks had worked with got tap water.
He analyzed the tap water from
previous labs and found it contained copper. When the rabbits
at Sun Health were fed tap water, they also developed Alzheimer's
When Sparks added copper to the
distilled water and gave the rabbits cholesterol, they also developed
Alzheimer's-like symptoms and brain lesions.
This does not mean that copper
pipes are bad, Sparks said.
"Metal pipes are inert. I could
throw a penny in a gallon of water and get no copper into the
water," he said.
But acid in the water can cause
copper to leach out.
Sparks checked for zinc, aluminum,
iron and other metals and did not find them consistently in the
drinking water his experimental rabbits were given.
Reference Source 89