Jan. 6, 2010 -- Cell phone exposure may be helpful in the fight against Alzheimer's disease, a new study shows.
The study, involving mice, provides evidence that long-term exposure to electromagnetic waves associated with cell phone use may protect against, and even reverse, Alzheimer's disease.
The study is published in the Journal of Alzheimer's Disease.
"It surprised us to find that cell phone exposure, begun in early adulthood, protects the memory of mice otherwise destined to develop Alzheimer's symptoms," study researcher Gary Arendash, PhD, of the University of South Florida, says in a news release. "It was even more astonishing that the electromagnetic waves generated by cell phones actually reversed memory impairment in old Alzheimer's mice."
The researchers say they found that exposing old mice with Alzheimer's disease to electromagnetic waves generated by cell phones reduced brain deposits of beta-amyloid. Brain plaques formed by the abnormal accumulation of beta-amyloid are hallmarks of Alzheimer's disease, which is why most treatments try to target the protein.
The study allowed scientists to isolate the effects of cell phone exposure on memory from other lifestyle factors, such as exercise and diet, the researchers say.
The study involved 96 mice, including mice genetically engineered to develop Alzheimer's disease and normal mice. Both the Alzheimer's mice and the normal rodents were exposed to the electromagnetic field generated by standard cell use for two one-hour periods daily for seven to nine months.
The mice didn't wear headsets, and no one held tiny phones to their ears. Their cages, rather, were arranged around a centrally located antenna generating the cell phone signal.
Each rodent was housed the same distance from the antenna and exposed to electromagnetic waves, at a level typically emitted by a cell phone pressed against a human head.
The researchers say that if cell phone exposure was begun when the Alzheimer's mice were young adults, and before signs of memory loss became apparent, their cognitive ability was protected. And if older mice with Alzheimer's were exposed, their memory impairment improved. What's more, months of cell phone exposure even boosted the memories of normal mice, the researchers write.
The researchers say the memory benefits in normal mice of cell phone exposure took months to show up, suggesting a similar effect in humans might take years. However, they also caution that "care should be taken in extrapolating our results to cell phone use and [electromagnetic wave] exposure in humans."
New Ways to Fight Alzheimer's and Brain Injuries
The researchers conclude that the findings could mean electromagnetic field exposure might be an effective, noninvasive, and drug-free way to prevent and treat Alzheimer's disease in humans.
"If we can determine the best set of electromagnetic parameters to effectively prevent beta-amyloid aggregation and remove pre-existing beta-amyloid deposits from the brain, this technology could be quickly translated to human benefit against AD [Alzheimer's disease]," says study researcher Chuanhai Cao, PhD, also of the University of South Florida. "Since production and aggregation of beta-amyloid occurs in traumatic brain injury, particularly soldiers during war, the therapeutic impact of our findings may extend beyond Alzheimer's disease."
Cao says the study "provides evidence that long-term cell phone use is not harmful to [the] brain," Cao says. "To the contrary, the electromagnetic waves emitted by cell phones could actually improve normal memory and be an effective therapy against memory impairment."
They note that previous human studies of electromagnetic waves from cell phones involved only brief exposures.
Although some people have claimed that cell phones may cause brain tumors, the South Florida researchers say that "despite numerous studies, there is no definitive evidence that high-frequency electromagnetic field exposure is a risk to human health" and their study suggests the waves may be beneficial.
A study published in December 2009 in the Journal of the National Cancer Institute found no substantial change in the incidence trend of brain tumors among a study group of 60,000 people five to 10 years after cell phone usage rose sharply in the countries where they lived.