“All of a sudden everything is dead in the water,” said Dale Kunkel, a communications professor at the University of Arizona who is an expert on children’s advertising. “I have heard no arguments to slow this down other than that the industry doesn’t like it.”

Among the requirements under consideration and included in a preliminary proposal by the agencies: Cereals could have only eight grams of sugar per serving, far less than many cereals that are heavily advertised to children (Lucky Charms and Cocoa Pebbles have 11 grams and Froot Loops has 12). The level for saturated fats would be set so low it would exclude peanut butter. And to qualify for advertising, all foods would have to contain significant amounts of wholesome ingredients like whole grains, low-fat milk, fruits or vegetables.

Critics have long complained that standards used by food manufacturers to designate healthy foods suitable for advertising to children are flawed, with ads for foods high in calories, fat, sugar and salt remaining a prominent part of the Saturday morning ritual on television. The Obama administration, as part of its campaign against childhood obesity, has also called on food companies to do more to ensure that advertising aimed at children is for healthier products.

The federal involvement took a step forward last year when Congress ordered the Federal Trade Commission, the Food and Drug Administration, the Agriculture Department and the Centers for Disease Control and Prevention to recommend standards for children’s food advertising.