14 Oct 2011

This Hour Takes 22 Minutes. Off Your Life.

By L E Carmichael

News.  Sit-Coms.  The Discovery Channel.  The latest "reality" drama.   No matter what you're tuning in to, you might want to turn it off.  According to a new study, television does more than rot your brain: it shortens your life.

A group of Australian scientists collected data from more than 11,000 people over the age of 25.  They compared the number of hours people spent watching TV every day to the number of years people lived.  The results were shocking.

A person who watches 6 hours of TV per day lives, on average, 4.8 years less than a person who watches no TV at all.  Every hour of TV watched after age 25 is associated with a decline in life expectancy of 22 minutes. 

The researchers compared TV viewing time with other risk factors for reduced lifespan.  This is a chart I made, based on data mentioned in the study:

That's right - watching 6 hours of TV per day appears to be as dangerous as lifelong smoking.  And if you're thinking that no one watches 6 hours of TV per day, you're wrong - the average adult in the USA watches about 5 hours a day.  That's 35.5 hours per week spent watching TV.  Or put another way, almost as many hours as a full-time job.

It might be a little soon to go throwing away your remote control.  This study demonstrates a negative correlation - in science-speak, interdependence between two variables.  In other words, as TV-viewing time increases, lifespan decreases.  That doesn't mean that television, in and of itself, is directly responsible for early death.  Correlations are not the same as causes.  Indeed, two correlated variables may in fact be responding to the same underlying-and-as-yet-unidentified cause.

In the case of this study, that cause is most likely sedentary behaviour, also known as too darn much sitting around.  And that sitting isn't just done in front of the tube.  It's at work, in the car, eating at restaurants and typing out emails.

Excuse me.  I have to put my laptop down now, go out, and take a walk.


Alison Stevens said...

And the follow-up study should look into the number of hours spent in front of a computer/game system and how they correlate with life span. Great information! And on that note, I'm headed out for a walk, too. :)

Lydia Kang said...

That is a very interesting study. I hope it's not the same as being online for 6 hours a day...because then I'm in trouble.

New follower, hi!

Lindsey Carmichael said...

Hi Lydia! Thanks for stopping by.

The next step in the research is to look for a causal connection between TV and loss of lifespan, and to test for correlations to other sedentary behaviours, like computer use.

As an interesting aside, one trend spreading among professional writers is the treadmill desk, which allows typing and walking at the same time. If you drop by Arthur Slade's website, he's posted pictures of his!