(Ivanhoe Newswire) -- Parents know kids aren't as healthy when they watch too much television because it keeps them from exercising or keeps them snacking in front of the television, but new research shows TV watching may actually impact fruit and vegetable consumption among adolescents.

Harvard researchers found each hourly increment of TV viewing was associated with a decrease in fruit and vegetable consumption among adolescents. They found the more television the teens watched, the fewer fruits and vegetables they ate. The authors studied the eating and TV viewing habits of teens for nearly two years. They say a young person who watched television three hours a day in the beginning of the study and increased his or her viewing by one hour a day had, on average, 2.25-fewer servings of fruits and vegetables per week. That means these kids are getting about 110 fewer servings of fruits and vegetables per year than those who do not watch television. The researchers say, "In sum, fruit and vegetable consumption was negatively associated with hours of television viewing."

The researchers have several theories for their findings. First, they point to previous studies that show children ages 2 to 11 are exposed to an average of 150 to 200 hours of commercial messages (or 20,000 commercials) each year, and nearly 56 percent of these ads are for food. Other studies have shown that nearly half of food commercials aimed at kids have implicit messages that the foods are healthy or nutritious, including ads that market sugary breakfast cereals as part of a "balanced diet." This study reveals children's nutritional knowledge may be biased by these marketing strategies. Plus, since the people kids see on television are rarely obese or suffering from poor health caused by bad dietary habits, kids may have unrealistic expectations about the consequence of bad eating habits.

The U.S. Department of Agriculture's Food Guide Pyramid recommends three to five servings of vegetables each day. Most surveys estimate kids eat between 2.2 and 2.4 servings daily -- well below those guidelines. In addition, 25 percent of the reported "vegetables" eaten by children and adolescents are french fries. This study shows only one in five children consumes five or more servings of fruit and vegetables each day.

The Harvard researchers say children should be made aware of the goal of commercials so that they become informed consumers. They also say parents need to try to stick to the American Academy of Pediatrics recommendation of no more than two hours of television per day. They write, "It is essential that parents are informed of the potential impact television viewing may have on their children."

SOURCE: Pediatrics, 2003;112:1321-1326

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