According to researchers in the U.S. there is a direct link between childhood obesity and junk food advertising on television.

A team of researchers from the Harvard School of Public health (HSPH) and the Children’s Hospital in Boston have found that children who spend more time watching TV were more likely to eat more of the calorie-dense, low nutrient foods advertised on television.

The association between childhood overweight and television viewing, has being explored previously in studies but the conclusion has more often than not been that it is the physical inactivity associated with television viewing which is the contributing factor.

But this study has found that children who watch the most TV ate the most junk food which indicates that junk food ads play a role in the ever-increasing trend of childhood obesity in the U.S.

Jean Wiecha PhD, the study’s lead author and a senior research scientist at HSPH says the study is evidence that television is effective in getting kids to eat the foods that are advertised.

In the study, Wiecha and her colleagues surveyed 548 students in sixth and seventh grade in five public schools in 4 communities near Boston.

They examined their dietary patterns including use of sweet baked snacks, candy, fried potatoes, main courses commonly served as fast food, salty snacks, and sugar-sweetened beverages commonly advertised on television, along with their television viewing habits and the number of hours spent watching television each day of the week.

When they did the survey again 19 months later longer television viewing was associated with higher intake of calories, one hour television viewing increasing consumption of 167 calories which says Wiecha equates with the amount of calories in a soda or a handful of snack food.

According to the study, each additional hour of television viewing was independently linked with an increased consumption of foods commonly advertised on television, which were responsible for much of the calorie increase.

The link between viewing time and sugar-sweetened beverages was the strongest.

Experts say obese children run the risk of diseases such as diabetes and heart disease in their adulthood and reduce their life expectancy.

The study supports the advice of the American Academy of Pediatrics who recommend that children’s television watching time should be limited to less than two hours a day to both reduce sedentary time, a risk factor for childhood overweight, and reduce exposure to content associated with negative consequences.

This research is published in the current edition of the of the Archives of Pediatric and Adolescent Medicine.