Study: Older Walkers Cut Dementia Risk

Older adults who regularly walk at least 6 miles a week may be less likely to develop dementia, a study suggests. The study included nearly 300 adults. Their average age was 78. Researchers asked them how many blocks they walked each week. Nine years later, they were given magnetic resonance imaging (MRI) scans to measure brain volume. People who walked at least 72 blocks a week (6 to 9 miles) had more gray matter in the brain. Then, 4 years after the MRI, people were given tests related to cognitive ability (thinking and memory). The tests showed about 40% had either dementia or a mild cognitive impairment, which can lead to dementia. But people with more gray matter were only half as likely as others to have these problems. There was no benefit for people who walked fewer than 6 miles a week, researchers said. The journal Neurology published the study online.