TV Watching, Physical Inactivity as Young Adults = Poor Cognition Later

Watching TV. Steven Puetzer Photographer's Choice/ Getty Images

Research presented at the Alzheimer's Association International Conference 2015 found an interesting correlation between time spent watching TV in early adulthood and cognitive functioning more than 25 years later. This same study also found that low physical activity levels as early adults also were tied to decreased cognition in mid-life.

The Study

This research, which was part of the Coronary Artery Risk Development in Young Adults Study, involved 3,247 adults between the ages of 18 and 30 years old at the time of its beginning in 1985.

Their patterns of TV watching and levels of physical activity were documented periodically over 25 years through the use of a questionnaire.

At the end of of the 25-year study, the participants' cognitive functioning was evaluated using three assessment tools:

A high level of TV watching was defined as greater than 4 hours a day, on average, while a low level of physical activity was defined as less than 300 Calories (kilocalories) for 50 minutes, 3 times a week. The participants were classified as having either a high level of TV watching or low level of physical activity level if they fit the above criteria at least 2/3 of the time throughout the 25-year period.

The Results

At the conclusion of the study, 11% of the participants reported high TV viewing, 17% reported low physical activity level and 3% fell into both of these categories.

The cognitive performance scores of the high TV viewing group and the low physical activity group were both significantly lower than those with lower TV viewing and higher physical activity levels.

Additionally, participants who reported both high TV viewing and low physical activity levels were more than twice as likely as those with neither of these risk factors to perform poorly on the cognitive tests.

Here's my simplified version of the results:

  • High amounts of tv = risk of lower cognitive ability
  • Low amounts of physical activity = risk of lower cognitive ability
  • High amounts of tv + low amounts of physical activity = very high risk of lower cognitive ability

The Take Away?

In this time where electronics and screens are everywhere-- televisions, tablets, smart phones, etc.-- it's wise to temper their use with genuine social interaction, physical exercise and mental activity. 

Previous research studies have identified social interaction, mental activity, physical exercise and diet all as important factors in reducing the risk of dementia. Interestingly, many of those studies reinforce the results of this study in concluding that patterns and activities earlier in life have lasting impacts later in life.

And, since your brain can't be replaced the way your hip or knee can, it would be wise to invest some time and energy into taking good care of it, while you can.

Related Resources


Alzheimer's Association International Conference 2015. July 20, 2015. Low Physical Activity and High TV Viewing are Associated with Worse Cognitive Function.

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