Too much TV and sitting lower brain power with time

You may want to start monitoring your couch potato-ness as a new study suggests that sitting around watching TV and not doing any physical activity as a young adult may cause a decline in brain functioning even earlier than scientists had thought.

Watching a lot of TV and having a low physical activity level as a young adult were associated with worse cognitive function 25 years later in midlife, according to the study.

Tina D. Hoang of the Northern California Institute for Research and Education, Kristine Yaffe of the University of California, San Francisco, and coauthors examined associations between 25-year patterns of television viewing and physical activity and midlife cognition.

They said that in this biracial cohort followed for 25 years, they found that low levels of physical activity and high levels of television viewing during young to mid-adulthood were associated with worse cognitive performance in midlife.

In particular, these behaviors were associated with slower processing speed and worse executive function but not with verbal memory. Participants with the least active patterns of behavior (i.e., both low physical activity and high television viewing time) were the most likely to have poor cognitive function. Individuals with both low physical activity and high sedentary behavior may represent a critical target group, the study concludes.

The study is published online by JAMA Psychiatry.