For the aging population, medical professionals often suggest walking as a low-impact, low-cost method of staying active. The health benefits of higher step counts in aging adults are well known, with research showing high step counts can reduce the risk of death, cardiovascular disease, and cancer. A suggested “optimal dose” of 6000 – 8000 steps per day has been identified in various studies as an ideal and attainable goal for most aging adults. While a high daily step count has been linked to reduced risk of death and many types of diseases, the question of whether higher step counts can be beneficial for the aging brain was not previously well researched by scientists.
Recently, a team of researchers from the University of Southern Denmark and the University of Sydney investigated the relationship between daily step counts and different kinds of dementia. Dementia refers to a loss of memory, language, problem-solving, and other cognitive skills that are enough to interfere with daily-life. Alzheimer’s disease is the most common cause of dementia. The team conducted what is known as a prospective cohort study, which is a type of epidemiological study in which a group of individuals are tracked over a set time period to determine whether a certain characteristic (step count in this case) will affect a certain outcome (dementia in this case).
The team examined data from the UK Biobank, a large-scale database with health information from half a million UK citizens. From the UK Biobank, there were 236,519 participants who provided a valid email address, excluding those who could not be contacted. 103,684 of these accepted the invitation to participate in the study, and were instructed to wear a wrist accelerometer (similar to a FitBit) for 24 hours a day, 7 days a week in order to measure their step counts. Participants were excluded on the basis of having invalid accelerometer data or major health problems.
After all the screening, a total of 78,430 participants between the age of 40–79 were included in the study. The average age of the participants was 61.1 years, with 35,040 (44.7%) participants being male, while 43,390 (55.3%) were female. These participants were monitored for dementia that started during the study period for a median time of 6.9 years, until October 31, 2021.
The researchers found an association between steps and lower dementia incidence. The “optimal” number of steps identified in this research was 9826. This means that a level of 9826 steps was associated with a dementia diagnosis at roughly half the rate of the participants that were inactive. The minimum number of steps in order to start seeing a benefit was 3826. In addition, these researchers found that patients who took more steps per minute, or walked faster, were also less at risk for getting dementia. In fact, a higher intensity of steps (walking faster) strengthened the association between step counts and reduced dementia risk.
While walking more matters, walking with a purpose, such as in exercise, was also important. The researchers suggest that step count guidelines may be particularly beneficial as they are easy to communicate, interpret, and measure. This research now adds to multiple lines of evidence which suggests daily walking and having higher step counts is a healthy endeavor, not only for general aging, heart health, and cancer prevention, but also for brain health.
