Socio-economic factors associated with the iron intake of preschoolers in the United States

Dietary intake in Head Start vs non-Head Start preschool-aged children: results from the 1999-2004 National Health and Nutrition Examination Survey

OBJECTIVE

To determine whether dietary intakes of children enrolled in Head Start programs differ from those of children not attending preschool or children in non-Head Start programs.

DESIGN

Using data from the 1999-2004 National Health and Nutrition Examination Survey, low-income, 3- to 5-year-old children were categorized into one of four preschool groups: Head Start (n=184), non-Head Start (n=189), past preschool (n=193), and no preschool (n=384). Total nutrient intakes were calculated using 24-hour parental recalls.

STATISTICAL ANALYSES PERFORMED

Mean macronutrient and micronutrient intakes were compared across groups and the percentage of children not meeting Recommended Dietary Allowances (RDAs) were calculated. Multivariate logistic regression was used to evaluate the relationship between preschool group and likelihood of not meeting dietary guidelines.

RESULTS

Many children did not meet the RDA for folate (20.5%), vitamin A (39.7%), vitamin E (79.7%), calcium (40.2%), iron (28.8%), and potassium (90.8%). Compared with the other preschool groups, Head Start children had lower mean protein, saturated fat, riboflavin, calcium, and phosphorous intakes. The greatest differences in intake were observed between Head Start participants and no-preschool children. Multivariate analyses demonstrated an association between Head Start and inadequate intake of protein, thiamin, riboflavin, niacin, calcium, and selenium.

CONCLUSIONS

Compared with other low-income children, those in Head Start programs appear to be at greater risk for not meeting the RDA for several key vitamins and minerals. These differences in diet quality may present an opportunity for Head Start programs to enhance nutrition in this student population.

Bioavailability, absorption mechanism, and toxicity of microencapsulated iron (I) sulfate: studies in mice

The iron compounds used for food fortification have to meet certain requisites related to their bioavailability, absorption mechanism, and toxicity, since they will be consumed by a massive population group. With these purposes, we evaluated a new product used for the iron fortification of milk and lacteous derivatives, called SFE-171, which is a ferrous sulfate, microencapsulated with phospholipids. The bioavailability studies were carried out using four groups of 30 female mice each. In two groups, we studied the absorption of ferrous ascorbate and ferrous sulfate, both in water as reference standards, which show absorptions of 13.1+/-4.9% and 13.2+/-4.3%, respectively. With the third group, we studied the absorption of ferrous sulfate in milk; its value, 7.9+/-3.2%, is significantly lower than that of the remaining groups, with a p < 0.01. The studies with SFE-171 in milk, were performed on the fourth group, with a result of 11.6+/-4.5%, demonstrating that its absorption does not differ significantly from that of the reference standards. The absorption mechanism was determined by means of in vivo self-displacement studies of the ferrous ion and the SFE-171, taking ferrous sulfate as the reference compound. For this study, 210 female mice were used, and no significant difference between the absorption mechanism of both products could be observed. Toxicity studies of the new product with regard to ferrous sulfate were carried out with two groups of 70 female mice each and two groups of 70 male mice each. The lethal dose 50% LD50 for SFE-171 and for ferrous sulfate was 1200 and 680 mg/kg for female mice and 1230 and 670 mg/kg for male mice, respectively, demonstrating that the toxicity of the first product is substantially lower than that of the reference standard. We conclude that the iron product under study has a high bioavailability, an absorption mechanism equal to that of nonhemic iron, and lower toxicity than ferrous sulfate.