A new study published in Alzheimer’s & Dementia: The Journal of the Alzheimer’s Association has revealed that prolonged periods of sitting are significantly associated with cognitive decline and brain shrinkage linked to Alzheimer’s disease—even in individuals who exercise regularly.
This research provides important insights into how everyday habits like sedentary behavior may play a crucial role in brain health as we age.
Researchers from Vanderbilt University Medical Center and the University of Pittsburgh conducted a comprehensive analysis involving more than 400 adults aged 50 and older.
The study methodology was particularly robust, as participants wore activity-tracking devices for ten consecutive days, providing detailed data on their sedentary behavior.
The researchers then analyzed this data against cognitive tests and brain imaging over an extended seven-year period, allowing them to track changes over time.
One of the most striking findings was that individuals carrying the APOE-e4 allele—a known genetic marker for Alzheimer’s disease—were particularly vulnerable to the negative effects of sedentary behavior.
These individuals experienced greater cognitive decline and notable shrinkage in brain regions critical for memory and Alzheimer’s development when they engaged in more sedentary behavior.
What makes this study particularly noteworthy is that the negative effects of prolonged sitting were observed regardless of participants’ exercise routines. In fact, the sample of participants was quite active, with 87% meeting the CDC recommendation of at least 150 minutes of moderate to vigorous physical activity per week.
This suggests that even regular exercise cannot fully counteract the detrimental effects of extended sitting time.
Lead researcher Marissa Gogniat emphasized this point, telling Consumer Reports, “Reducing your risk for Alzheimer’s disease is not just about working out once a day. Minimizing the time spent sitting, even if you do exercise daily, reduces the likelihood of developing Alzheimer’s disease.”
These findings have significant implications for healthcare professionals and aging adults. The researchers suggest that healthcare providers might consider assessing not only a patient’s exercise regimen but also the amount of time they spend being sedentary throughout the day.
This is particularly important in the context of aging, as mobility limitations and greater sedentary time typically increase in older adults.
The study builds on previous research suggesting that “sitting is the new smoking,” indicating that a sedentary lifestyle is detrimental to overall health.
A JAMA Network study published last year followed nearly 500,000 people for 12 years and found those who sat at work had a 16% higher risk of mortality from all causes and a 34% higher risk of heart disease compared to those who predominantly didn’t sit at work.
However, there is some hope. Another study, published in 2023 in the British Journal of Sports Medicine, found that just 22 minutes of brisk walking or a similar activity could offset the risk of prolonged sitting.
This suggests that even small changes in daily habits could have significant benefits.
With nearly seven million people in the U.S. currently living with Alzheimer’s, and the number expected to reach 13 million by 2050 according to the Alzheimer’s Association, understanding modifiable risk factors like sedentary behavior becomes increasingly important for public health strategies.
