A new study examining mental activity in sedentary positions found a correlation between mentally passive activities and an increased risk of developing dementia. This is compared with more engaging mental activities, regardless of how physically active a person is while standing.

In other words, not all sedentary behavior (SB) is created equal. Mentally passive activities include watching TV or scrolling social media, whereas computer use or solving puzzles would be considered more mentally active.

For the study, the health records of over 145,000 UK participants were analyzed, all of which were over 60 years old. At the time of the analysis, none of the participants had a dementia diagnosis. Researchers tracked their TV watching and computer use habits for almost 12 years. At the end of this period, over 3,500 of them had developed dementia, and researchers could identify patterns of mental behavior as a driving force in developing the disease.

Dr. David Raichlan of the University of Southern California told Medical News Today: “This cohort is really amazing. What happens when you have [so many] people is you’re able to end up with several thousand cases of dementia. Then you can start to see what are some of the stronger associations. A lot of studies with a smaller group end up, obviously, with fewer dementia cases to work with. This big group really gives us the ability to tease out some associations that you wouldn’t find in smaller surveys.”

It’s understandable that not all SBs are the same because our brain operates differently and uses different amounts of energy depending on how active or passive the task at hand is. “We know, for example, that the brain uses glucose differently when we are mentally active (reading, solving a puzzle/problem, etc.), compared to passive TV viewing.”— Dr. Mats Hallgren

Those involved in the study emphasized that more follow-up is needed around this study, and tracking more people over more extended periods will yield more conclusive data.

Additionally, there is no one cause for dementia but certain risk factors, with passive mental activity being one of them. Because the study is observational, it is not necessarily causational.