Young children who dig into a bowl of fortified breakfast cereal may be getting too much of a good thing.

A new report says that “millions of children are ingesting potentially unhealthy amounts” of vitamin A, zinc and niacin, with fortified breakfast cereals the leading source of the excessive intake because all three nutrients are added in amounts calculated for adults.

Outdated nutritional labeling rules and misleading marketing by food manufacturers, which use high-fortification levels to make their products appear more nutritious, fuel this potential risk, according to the report by the Environmental Working Group, a Washington, D.C.-based health research and advocacy organization.

Although the Food and Drug Administration is currently updating nutrition facts labels that appear on most food packages, none of its proposed changes address the issue of over-consumption of fortified micronutrients or that the recommended percent daily values for nutrition content that appear on the labels are based on adults, says Renée Sharp, EWG’s director of research.

Only “a tiny, tiny percentage” of cereal packages carry nutrition labels that list age-specific daily values, Sharp says. “That’s misleading to parents and is contributing to the problem.”

The daily values for most vitamins and minerals that appear on nutrition facts labels were set by the FDA in 1968 and haven’t updated, she says, making them “wildly out-of-sync” with currently recommended levels deemed safe by the Institute of Medicine, a branch of the National Academy of Sciences.

Getting adequate amounts of all three nutrients is needed to maintain health and prevent disease, but the report says routinely ingesting too much vitamin A can, over time, lead to health issues, such as liver damage and skeletal abnormalities. High zinc intakes can impair copper absorption and negatively affect red and white blood cells and immune function, and consuming too much niacin can cause short-term symptoms, such as rash, nausea and vomiting, the report says.

When combining food intake and vitamin supplements, the report calculates more than 10 million American children are getting too much vitamin A; more than 13 million get excessive too much zinc; and nearly 5 million get too much niacin.

EWG’s analysis of nutrition facts labels for 1,556 breakfast cereals and 1,025 snack and energy bars identified:

114 cereals fortified with 30 percent or more of the adult daily value (or recommended level of intake) for vitamin A, zinc and/or niacin.

27 snack and energy bars fortified with 50 percent or more of the adult daily value for at least one of the three nutrients.

23 cereals with added fortification of one or more of the nutrients in amounts “much greater” than the levels deemed safe for children age 8 and younger by the Institute of Medicine.

Cereals with the highest added nutrient levels include national brands such as Kellogg’s Product 19 and General Mills Total Raisin Brain, as well as store brands from Food Lion, Safeway and Stop & Shop.

In a statement, Kellogg spokesperson Kris Charles says, “The report ignores a great deal of the nutrition science and consumption data showing that without fortification of foods such as ready-to-eat cereals, many children would not get enough vitamins and minerals in their diets. Less than 2 percent of all cereals assessed by EWG made their “Top 23” list, and the vast majority of these are adult-oriented cereals not regularly consumed by children.”

The FDA, in a statement, said proposed daily values for infants (7-12 months) and young children (1-3 years) are being considered, but not for 4-8 year olds “because they consume the same foods as the general population,” and the FDA “is not aware of foods that are sold specifically for this age group.”

The agency added it is proposing lowering daily intakes for these nutrients for the revamped food labels.

The evidence that millions of children are exceeding the safe upper levels for some nutrients “is fairly good and traceable to excessive marketing-driven fortification,” says Susan Roberts, a professor of nutrition at Tufts University, who was not involved in the EWG report. “But right now, we don’t have a lot of evidence that it is creating massive health problems. Rather, I would say it is unnecessary, not health-promoting and, in some individual cases, may be causing toxic problems.”

To help reduce the amount of vitamin A, zinc and niacin that kids consume, EWG says parents should limit the fortified cereals and other foods kids eat to those containing no more than 20 percent to 25 percent of the adult daily value for each of the nutrients.

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