I’ve mentioned before that TV viewing can lead to weight gain for children, and now there’s an official policy statement from the American Academy of Pediatrics which reviews the evidence and offers advice to parents and doctors. Called “Children, Adolescents, Obesity, and the Media”, the bottom line is that there is indeed strong evidence that TV watching leads to weight gain and all the troubles this causes as adults — diabetes, heart disease, and arthritis, among many other illnesses. I think parents should read the PDF file here, and then have a long discussion with your kids. Here’s the abstract:

Obesity has become a worldwide public health problem. Considerable research has shown that the media contribute to the development of child and adolescent obesity, although the exact mechanism remains unclear. Screen time may displace more active pursuits, advertising of junk food and fast food increases children’s requests for those particular foods and products, snacking increases while watching TV or movies, and late-night screen time may interfere with getting adequate amounts of sleep, which is a known risk factor for obesity. Sufficient evidence exists to warrant a ban on junk-food or fast-food advertising in children’s TV programming.

Here’s some more hard data:

• a 30-year study in the United Kingdom found that a higher mean of daily hours of TV viewed on weekends predicted a higher BMI at the age of 30.
• For each additional hour of TV watched on weekends at age 5, the risk of adult obesity increased by 7%.
• In New Zealand, average weeknight TV-viewing between the ages of 5 and 15 years was strongly predictive of adult BMI.
• In a study of 8000 Scottish children, viewing more than 8 hours of TV per week at age 3 was associated with an increased risk of obesity at age 7.
• In 8000 Japanese children, more TV-viewing at age 3 resulted in a higher risk of being overweight at age 6.
• A study of 2343 children aged 9 to 12 years revealed that having a bedroom TV set was a significant risk factor for obesity, independent of physical activity.

The AAP has very specific advice for parents:

• No child should have more than 2 hours a day of total “non-educational” screen time (computers, TV, iPads, etc)
• Those under 2 should have ZERO screen time

This recommendation actually has some good data behind it. As they mention, studies showed that:

Children who did not adhere to the American Academy of Pediatrics guidelines of less than 2 hours/day of screen time and 11 000 to 13 000 pedometer steps per day were 3 to 4 times more likely to be overweight.

Preschool-aged children who ate dinner with their parents, got adequate sleep, and had limited screen-time hours had a 40% lower prevalence of obsity than those exposed to none of these routines.

The policy also has very strong recommendations for doctors taking care of kids;  we “need to ask 2 questions about media use at every well-child or well-adolescent visit:

1. How much screen time is being spent per day? and
2. Is there a TV set or Internet connection in the child’s bedroom?”

I think this AAP policy statement is an important step for public health. As a family doctor dealing with both childhood and adult obesity every day in my clinic, I’m very glad I have more and more evidence and backup from my peers; just last week I was blogging about another new study talking about obesity and lifestyle changes. This “war on obesity” is going to be a very long one, and we need all the help we can get.