(CNN) -- Most parents are concerned about their kids getting enough vitamins. Should they also worry about giving their kids too much?
A recent report published by the Environmental Working Group says children may be consuming too much vitamin A, zinc and/or niacin from some cereals, thanks to antiquated nutrition information on their labels.
The Food and Drug Administration sets the "daily value" percentages you see on nutrition labels. The total amount for each nutrient is based on recommendations for adults, the EWG saidsa, and the values haven't changed since 1968.
The Institute of Medicine updates their recommended daily values annually based on current nutritional information. IOM guidelines (PDF) state children between the ages of 4 and 8 should be consuming less than 0.9 mg of vitamin A, 15 mg of niacin and 12 mg of zinc each day.
In their report, the Environmental Working Group analyzed the nutrition labels of more than 1,500 breakfast cereals. They found 114 of the cereals -- about 7% -- contained a large percentage of the recommended daily value of vitamin A, zinc and/or niacin per serving.
EWG reported most children eat more than one serving of cereal -- typically defined as 3/4 cup -- in a sitting. So if children consume about 2.5 servings, they would meet or exceed the IOM's limit for these vitamins, even without consuming other foods that are fortified or taking a daily multivitamin.
The Grocery Manufacturers Association, which represents the food and beverage industry, said that fortification of foods has long been successful in helping consumers get the nutrients they need.
"The FDA has a robust and clear regulatory policy in place to ensure that fortification of foods is practiced safely and appropriately," said director of communications Brian Kennedy. "The IOM offers additional guidance for discretionary fortification of foods."
On EWG's "excessively fortified cereals" list are several brands of bran flakes, raisin bran and wheat flakes. While these may or may not appeal to the majority of children, the EWG said cereals are kids' No. 1 source for getting an excess of nutrients.
"EWG identified 23 excessively fortified cereals," said Olga Naidenko, co-author of the report. "Two brands of cereal, Kellogg's Krave and Kellogg's Cocoa Krispies, clearly have product labels that would appeal to children, with cartoon style writing and images."
But some experts say cereal isn't the biggest concern when it comes to kids' excessive vitamin and mineral intake.
A recent study found that 45% of children are getting too much zinc, 13% too much vitamin A and 8% niacin. If the child is taking multivitamins, those numbers are significantly higher: 72% of kids taking a multivitamin are overdosing on vitamin A, 28% are consuming too much niacin and up to 84% are getting too much zinc.
"Overdosing on vitamins or minerals typically occurs when a person takes too many supplements, rather than too much of a certain food," said Dr. Jennifer Shu, a pediatrician with Children's Medical Group in Atlanta.
In the short-term, excessive intake of some vitamins and minerals could lead to gastrointestinal symptoms, she said. The long-term effects of too much vitamin A, include liver and skeletal damage. Overdosing on zinc can lead to an impaired immune function, and excessive niacin is toxic to the liver.
"Parents may want to look at their kids' favorite cereals and bars to check the fortification levels and cut back if they have concerns about the amounts -- or any symptoms their child may have," Shu said.
To prevent excessive intake, the Environmental Working Group recommends parents usea caution when feeding children foods with more than 25% of the adult daily value and monitor their intake of all foods to make sure they're not getting an excessive amount, especially if the child is also taking multivitamins.
"The FDA needs to set percent DV levels that reflect current science," the report concluded.