Supplements fall short of children's needs

More than a third of children aged 2 to 18 years who take dietary supplements failed to meet intake recommendations for calcium and vitamin D but were at increased risk of intake above recommended levels for other vitamins and minerals, a new study reports.

Children aged 2 to 8 years had nutritionally adequate diets whether or not they took supplements. Without supplementation, however, the diets of children older than 8 years would have had inadequate amounts of magnesium, phosphorus, and vitamins A, C, and E.

Conversely, supplementation increased the likelihood of raising intake above tolerable upper levels for iron, zinc, vitamin A, and folic acid in children of all ages as well as for vitamin C, copper, and selenium in children aged 2 to 8 years. The long-term effect of high doses of nutrients in children is not known.

Researchers examined data on 7,250 children aged 2 to 18 years using the 2003-2006 data sets of the National Health and Nutrition Examination Survey. They evaluated participants’ dietary intake interviews and evaluated supplement use with a 30-day questionnaire. Then they compared the results with target micronutrient intakes from the Institute of Medicine’s dietary reference intakes and determined the prevalence of inadequate intakes using the estimated average requirements method.

Forty-two percent of children aged 2 to 8 years took supplements. Lower use of supplements was reported among 9- to 13-year-olds (29%) and 14- to 18-year-olds (26%). Children aged 14 to 18 years were most likely to have micronutrient deficiencies and least likely to be taking supplements.

The findings of the study suggest possible implications for reformulating dietary supplements for children, the researchers say. Particular attention should be paid to providing adequate levels of micronutrients such as calcium and vitamin D, which were insufficient in all children, and minimizing excess intake of other nutrients.

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