Kids' Vitamins Often Exceed Recommended Doses

Young children who take vitamins may be consuming much greater levels than recommended of the nutrients, a new study suggests.

For the research, scientists reviewed the labels of nearly 200 dietary supplements marketed for children in two age groups: younger than 12 months, and 1 to 4 years old. The researchers determined the level of vitamins that children would consume if they used the product as directed. (Specifically, they looked at levels of vitamins A, C, D, E, K and B12, along with thiamin, riboflavin, niacin, folate, biotin and choline.)

Most products contained vitamin levels much greater than those recommended for children in a single day. For example, dietary supplements for children ages 1 to 4 contained, on average, about 300 percent of the daily recommended levels of vitamin A, thiamin and riboflavin, 500 percent of the recommended level of vitamin C and more than 900 percent of the recommended level of biotin. [10 Ways to Promote Kids' Healthy Eating Habits]

Vitamin D was the only vitamin that was present at or below recommended levels for both age groups.

It's too soon to know whether these findings are concerning, said study researcher Michael Madden, an assistant professor at Lake Erie College of Osteopathic Medicine (LECOM) School of Pharmacy. That's because few studies have explored the effects of greater-than-recommended levels of vitamins on infants and young children. So in many cases, the maximum amount of a vitamin that's safe for a child to take is not known, the researchers said.

For this reason, the Institute of Medicine (IOM) recommends that young children not consume excess levels of certain vitamins, including vitamins K and B12, thiamin, riboflavin, folate, pantothenic acid and biotin. (Infants should not consume excess levels of most vitamins.) The IOM, part of the U.S. National Academies, is a national nonprofit that advised the nation on health.

There is also a concern that children's bodies may lack the ability to handle excess amounts of certain vitamins, the IOM says.

The findings suggests that "much of the pediatric vitamin supplementation is not based on IOM recommendations and therefore represents wholesale over-supplementation," the researchers wrote in the Jan. 27 issue of the journal JAMA Pediatrics.

Some studies have also shown that dietary supplements may contain levels of vitamins that are different from what's listed on the label.

The American Academy of Pediatrics (AAP) says parents should speak with their pediatricians about whether their young child may need to take supplements. Toddlers who eat a balanced diet should be getting adequate levels of most vitamins and so should not need supplements, the AAP says. And very high doses of some vitamins, such as vitamin A, may even pose risks because they can accumulate in the body, the AAP says.

But some children may need supplements if, for instance, they have selective eating habits, and therefore don’t get adequate levels of vitamins through food, the AAP says.

In addition, the AAP recommends vitamin D supplements for infants, children and adolescents so that they consume 400 International Units (IU) of vitamin D per day.

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