The World: Washington - Study criticises proliferation of junk-food ads

US children are being force-fed a diet of TV ads for sweets, snacks and fast food, which are crowding out spots for healthy products, according to a new study.

The Kaiser Family Foundation estimates that children aged between eight and 12 - the so-called "tweens" - see an average of 21 such ads a day, or 7,600 a year. Teenagers see an average of 17 a day, or about 6,000 a year.

Vicki Rideout, the foundation's vice-president, said: "Since 'tweens' are at an age where they're just becoming independent consumers, understanding what type of advertising they are exposed to is especially important."

Last November, companies including McDonald's, Coca-Cola and PepsiCo, agreed to devote at least half of their advertising directed at children to promote healthier diets and lifestyles.