Exercise is good for general health but there’s new evidence that it is especially beneficial to the aging population that is at increased risk of Alzheimer’s and other forms of dementia.
A new Columbia University Irving Medical Center study, co-led by Dr. Ottavio Arancio, found evidence that exercise produces another hormone that may improve memory and protect against Alzheimer’s disease.
The hormone is called irisin and is released into the bloodstream during physical activity. This hormone plays a role in energy metabolism but now researchers believe to also promotes the growth of cells in the region of the brain critical for learning and memory.
“This raised the possibility that irisin may help explain why physical activity improves memory and seems to play a protective role in brain disorders such as Alzheimer’s disease,” said Arancio, who is a professor of pathology and cell biology and of medicine at Columbia University Vagelos College of Physicians and Surgeons.
Over the years, other researchers have suggested that exercise might be a way to reduce the risk of dementia.
According to Dr. Frank Longo, chairman of the Department of Neurology at Stanford Hospital, each of us has a 5 percent lifetime risk of getting dementia. Having one parent with dementia makes it three times more likely. But there may be ways to reduce your risk.
“There are a considerable number of studies that physical exercise makes a big difference,” said Longo in a press release. “People who are physically active have about a 40 or 50 percent reduced likelihood of coming down with Alzheimer’s and related dementias. That’s a huge effect.”
In this latest study, Arancio and his colleagues at the Federal University of Rio de Janeiro in Brazil and Queens University in Canada first looked for a link between irisin and Alzheimer’s in people. Using tissue samples from brain banks, they found that irisin is present in the human hippocampus and that people with Alzheimer’s much smaller amounts of the hormone in their brain.