Positive fast food imagery on television can lead to negative influences on childhood behavior and values, according to a recent study.

Researchers from American University found that people who watch TV frequently believe that fast food consumption has more positive consequences and fewer negative consequences than light viewers. In other words, young people who watch a lot of TV exhibit increased positive perceptions of eating fast food and perceive less health risks. As a result, such biased perceptions may result in increased fast food consumption and thus indirectly contribute to the growing obesity crisis.

However, they found that the strength of the relationship between positive fast food exposure on TV and risk experiences decreases as actual experience with fast food increases.

"While personal experience of consuming fast food would lead one to more directly witness and believe the negative outcomes associated with its consumption, those with less personal experience are more susceptible to the influences of TV," researcher Cristel Russell said in a statement.

For the study, researchers collected and analyzed data from more than 1,000 teenagers who reported hours of TV viewing, beliefs about the consequences of eating fast food, and their frequency of fast food consumption.

In addition to the finding that the amount of TV exposure influences audiences' beliefs about health risks of fast-food consumption, the study also revealed that heavy TV viewers who rarely ate fast food are especially desensitized to the health risk consequences of unhealthy eating. In contrast, young people who regularly ate fast food had an awareness of the health risks associated with eating poorly.

"Given the strong association between TV viewing and unhealthy eating habits among youth, public health researchers and practitioners should carefully monitor and perhaps regulate the amount of fast-food advertising on TV and the content of TV programs," Russell command. "Accurate portrayals of food consumption and its consequences are necessary to correct misperceptions among heavy TV viewers. Portrayals of positive food habits, such as the consumption of fruits and vegetables, in youth-oriented programming should also be encouraged, as previous experimental research has shown that such product placements can influence viewers' attitudes toward healthful food."

The findings are detailed in the journal Appetite.