American researchers have discovered that fast food companies, promoting children's meals on TV with ads that feature usage of toy premiums, may prompt children to request eating at fast food restaurants, a study suggests.

The research team found that the more children watched television channels that aired ads for children's fast food meals; the more frequently their families visited those fast food restaurants.

Using a database, the team compiled all fast food TV ads that aired nationally in 2009 in the US. Jennifer A. Emond and colleagues from the Geisel School of Medicine, Dartmouth enrolled 100 children (3 to 7) and one of their parents in the study.

The parents completed a survey that included questions about how often their children watched each of the four children's networks, if their children requested visits to the two restaurants, if their children collected toys from those restaurants, and how often the family visited those restaurants.

Researchers found that 37% of parents reported more frequent visits to the two fast food restaurants with child-directed TV ads.

Furthermore, 54% of the children requested visits to at least one of the restaurants. Of the 29% of children who collected toys from the restaurants, almost 83% requested to visit one or both of the restaurants.

Some factors associated with more frequent visits were more TVs in the home, a TV in the child's bedroom, more time spent watching TV during the day, and more time spent watching one of the four children's networks airing the majority of child-directed ads.

The findings also showed that children's food preferences may be partially shaped by a desire for the toys featured in TV ads.

"Our best advice to parents is to switch their child to commercial-free TV programming to help avoid pestering for foods seen in commercials," Emond said.

The study is scheduled to be published in The Journal of Paediatrics.