Updated

Television may be making it harder for kids to understand what’s healthy and what’s not when it comes to their diet.

A new study shows that children equate terms like “diet” and “fat free” with healthy because TV commercials equate weight loss benefits to nutritional benefits.

But what’s good for helping an adult lose weight won’t necessarily meet the nutritional needs of growing children.

"Given the plentitude of advertisements on television touting the health benefits of even the most nutritionally bankrupt of foods, child viewers are likely to become confused about which foods are in fact healthy," says researcher Kristen Harrison, a professor of speech communication at the University of Illinois at Urbana-Champaign, in a news release.

“We know that many American children are consuming too much fat and too many calories, but replacing the nutrient-dense foods in their diets with low-fat, low-calorie items like rice cakes and diet soda does them a disservice by depriving their bodies of the whole-food nutrients needed for growth," says Harrison.

Read WebMD's "Soft Drinks: Scapegoat for Kids' Obesity?"

TV Confuses Kids’ Food Choices

In the study, researchers tried to measure children’s understanding of which foods would help them grow by providing valuable nutrients rather than make them slimmer. The results appear in a recent issue of Health Communication.

More than 100 children in the first through third grade answered a questionnaire that assessed their nutritional knowledge, nutritional reasoning and television viewing. They completed the questionnaire once at the start of the study and again six weeks later.

To measure their nutritional knowledge, the children were asked to choose which item in six different pairs of foods was better for helping them "grow up strong and healthy." One food in each pair was more "nutritionally dense" than the other.

The study showed that the more television the children watched, the more confused they were about which foods are and aren't going to help them grow up strong and healthy.

"When they were presented with choices like Diet Coke vs. orange juice and fat-free ice cream vs. cottage cheese, they were more likely to pick the wrong answer -- the diet and fat-free foods -- than when they were presented with choices without these labels, for example, spinach vs. lettuce,” says Harrison.

Researchers also found that the more TV the children watched, the less likely they were to provide sound nutritional reasons, such as “More juicy, has vitamins (referring to celery). Instead, they were more likely to give reasons like, “It won’t make you fat (referring to fat-free ice cream),” or “It’s diet” (referring to Diet Coke).

Overall, the study showed that the children displayed “moderate” nutritional knowledge and scored an average of about 4 out of 6 on the test.

Read WebMD's "Kid Nutrition: Quick Tips for Parents"

By Jennifer Warner, reviewed by Charlotte E. Grayson, MD

SOURCES: Harrison, K. Health Communication, 2005; vol 17: pp 117-132. News release, University of Illinois at Urbana-Champaign.