How many hours a day do you sit? Well, new research has suggested there is a strong link between prolonged periods of inactivity and dementia.

The warning and health risks surrounding a sedentary lifestyle are no secret but it is still a concern with half of Australians spending most of their day sitting down – particularly older people living in residential aged care.

American researchers in Southern California and Arizona have now found that for those over 60-years-old, sitting for 10 hours or more a day increases your chances of experiencing all-cause dementia by 10%.

Being sedentary for 12 or more hours increased that risk further to a huge 65%.

“Hopefully, this kind of work can help people think more about how they’re spending their time,” University of Southern California researcher, Professor David Raichlen says.

Inactivity is associated with poor cardiovascular health and unhealthy blood pressure levels, which is linked to a higher risk of dementia. Similarly, physical activity reduces inflammation and insulin resistance, which may help reduce dementia risk.

With this in mind, experts suggest older people regularly do thirty minutes worth of cardiovascular exercise at moderate-intensity levels to reduce their risk of developing dementia.

The study builds on previous research, which used self-reported health data to investigate how certain types of sedentary behaviour, like sitting and watching TV, affect dementia risk more than others. Researchers said more study is needed to further determine the link between sedentary lifestyles and dementia risk.


  • The study observed almost 50,000 adults from the United Kingdom aged 60 or older who didn’t have a dementia diagnosis at the time.
  • Participants began wearing a wrist accelerometer from February 2013 – 2015 through to 2018 – 2022 while being consistently monitored
  • After an average of six years of follow-up, researchers used Artificial Intelligence (AI) machine learning to decipher sedentary patterns and compared it to inpatient hospital records and death registry data to determine dementia diagnosis