Everyone knows that breakfast is the most important meal of the day. A new study shows that cereals might not be the best choice for your child’s breakfast.

To be more precise, a serving of 11 popular cereals, including Kellogg’s Honey Smacks, carries as much sugar as a glazed doughnut, a new investigation from Consumer Reports said. A serving of Honey Smacks has 15 grams of sugar, 3 more grams that was found in a Dunkin’ Donuts glazed doughnut, and just one gram of fiber per serving. Post Golden Crisp made by Kraft Foods Inc and Kellogg's Honey Smacks are more than 50 percent sugar by weight, the group said. Cheerios and Kix had only 3 grams of fiber per serving, and Life and Honey Nut Cheerios were found to have 2 grams of fiber per serving, the report found.

Cereals sitting on the other side of the morning table were Raisin Bran, with 5 grams of fiber per serving, Grape-Nuts, with 7 grams, or Kashi Go Lean Crunch, with 9 grams. They were judged as good breakfast choices because they were relatively low in sugar and sodium, but were good sources of calcium and iron, and had some fiber. A 5-year-old should eat at least 10 grams of fiber a day.  

The list of cereals rated as “Very Good” breakfast choices included Cheerios (General Mills) with just 1 gram of sugar, 3 grams of fiber, and 190 milliograms of sodium, Kix (General Mills), with 3 grams of sugar, 3 grams of fiber, and 210 milligrams of sodium, Life (Quarter Oats), which has 6 grams of sugar, 2 grams of fiber, and 160 milligrams of sodium, and Honey Nut Cheerios (General Mills) with 9 grams of sugar, 2 grams of fiber, and 190 milligrams of sodium.  

“If you’re shopping for a kids’ cereal, try one of the Very Good cereals in our ratings,” said Gayle Williams, deputy editor of Consumer Reports Health. “Be sure to read the product labels, and choose cereals that are high in fiber and low in sugar and sodium. Served with milk and fruit, these cereals can be part of a well-balanced, nutritious breakfast.”

Froot Loops, Corn Pops, Rice Krispies, Cocoa Krispies, and Apple Jacks were among lowest-rated cereals, with 12 grams of sugar, one gram of fiber and 135-200 milligrams of sodium in a 3/4 coup of serving.

The report also found that an estimated 58 percent of kid’s cereals are eaten by adults. Consumer Reports studied how 91 children aged 6 to 16 ate their cereal and found they served themselves about 50 to 65 percent more on average than the suggested serving size for three of the four tested cereals.

The report found that some brands contain even more sugar and sodium when made for consumers in the U.S. than for consumers in other countries.

Consumer International said it would ask the World Health Organization to revise its international guidelines restricting advertising and marketing of foods high in sugar, fat or sodium to children.