Breakfast cereals for children increasingly contain more whole grains and less sugar, but U.S. food companies have focused advertising on their least healthy offerings to kids, a new study suggests.

Researchers at Yale University’s Rudd Center for Food Policy & Obesity checked into the nutritional quality and marketing of cereals for their Cereal Facts report.

Cereal companies have made small improvements to the nutrition of products targeted to children. (Ryan Remiorz/Canadian Cereal)

Overall, nutritional quality improved for 13 of the 14 brands advertised to children.

For 22 varieties of cereal that were available in the U.S. in both 2008 and 2011, 45 per cent had less sodium, 32 per cent had less sugar, and 23 per cent had more fibre, the researchers said.

At the same time, cereal makers increased advertising directed at children for some of their least nutritious products:

• Children saw more TV ads for the remaining seven child-targeted brands, including Reese’s Puffs, Froot Loops, and Pebbles.
• Post launched a new Pebbles "advergame" website, and General Mills launched new sites for Honey Nut Cheerios and Cinnamon Toast Crunch.
• Kellogg nearly doubled banner advertising on children's websites, such as Nickelodeon.com and Neopets.com, for its child-targeted brands.

The report's authors concluded that cereal companies have made small improvements to the nutrition of products targeted to children, but those cereals are still far worse than the cereals marketed to adults.

Regular Cheerios and Frosted Mini-Wheats have some of the highest nutrition scores, but ads for those products are more likely to be targeted at adults, the report said.

"It is obvious that industry regulating itself is a failure. If there is to be any hope of protecting children from predatory marketing, either public outcry or government action will be necessary to force the companies to change," study co-author Kelly Brownell, director of the Rudd Center, said in a release.

Before 1999, some cereals had up to 16 grams of sugar and now most have no more than 10 grams per serving, the Better Business Bureau's Children's Food and Beverage Advertising Initiative said.

The group includes Kellogg, General Mills and Post, which have agreed to follow nutritional criteria for products they advertise to children under the age of 12.

The findings will be presented on Sunday at the Society for the Psychological Study of Social Issues conference in Charlotte, N.C.