Screens: When more is harmful

Jean Rystrom, my friend and fellow member of the Healthy Kids Watch Less TV coalition, once again has shared some of the 2007 research that bears on our interest in the consequences of excessive screen time for kids. Jean is Kaiser-Permanente Northwest's regional practice director for pediatrics.

Here is what she has written us:

This is the last of my series of brief impressions from important medical studies in 2007 pertaining to screen time. Consider all of the usual caveats: I'm not a researcher, and I "might" be biased.

The first message simply updated the status quo: By age 12 months, the average baby is watching about 1 hour per day, despite the American Academy of Pediatrics recommendation of no screen time before age 2.

The second message showed significant delay in language acquisition associated with screen time in very young children, and sustained exposure was associated with problems in aggression (by far the strongest), sleep, self control, attention and cooperation.

The third message looked at the rapidly growing information about attention issues, where there is still much controversy. But it appears that there is some sort of connection, perhaps a tendency to become accustomed to rapid pacing from entertainment media, which leads to boredom with the real world.

Now, finally, the news on obesity, hypertension, and one article that ties together the issues with media, sleep and learning.

Obesity:

* Family eats together, more likely to serve fruits or veg

* Television on, less likely to serve fruits or veg

* Having dinner together does not overcome the adverse effects of having the television on during mealtime in terms of fruits and veg

Fitzpatrick et al, Journal of the American Dietetic Association, April 2007

Hypertension:

Looking at children who are obese, researchers found that both severity of obesity and daily TV time were significant independent predictors of the presence of hypertension.

* As is well supported elsewhere, TV time was positively correlated with the severity of obesity.

* Children watching 2-4 hours per day had 2.5 times the odds of hypertension compared to those watching less (adjusted for BMI, race, and site, but not SES), and 3.3 times the odds for over 4 hours per day of watching.

* The odds of having hypertension increased by 26 percent for each hour of TV watched per day.

Pardee, et al, American Journal of Preventive Medicine, December 2007

Sleep, memory and learning:

Very small German study in which 13 year old boys were given sleep studies and memory tests on 3 separate days: a) after 1 hour of "mild violence" video game, b) after a PG movie, and c) no screen time.

* Significant changes in sleep patterns were found the night after the video game and the movie, with greater changes for the computer game than the movie (hypothesis: the movie was pretty ho-hum for these boys, who are generally unrestricted in their viewing)

* The sleep pattern changes seen may be related to the learning "consolidation process" which takes place during sleep

* Verbal memory performance was much lower after the video game and also after the movie (but not quite statistically significant for the movie)

* The effect of media on sleep patterns could explain some of the negative association between school performance and screen time

Dworak et al, Pediatrics, November 2007