Longitudinal Assessment of Micronutrient Intake among African-American and White Girls: The National Heart, Lung, and Blood Institute Growth and Health Study

Abstract

Objective Low intakes of micronutrients among adolescents may be linked to long-term health risks, especially in African-American girls. This report describes intake of key micronutrients relative to the Dietary Reference Intakes in a sample of African-American and white girls. Design Longitudinal analyses used data from 3-day food records collected in the National Heart, Lung, and Blood Institute Growth and Health Study. Subjects/setting Subjects included 1,166 white and 1,213 African-American girls (aged 9 to 18 years). Main outcome measures Estimated usual daily intakes of vitamins A, E, C, D, B-6, B-12, magnesium, folate, calcium, and zinc were compared to the Adequate Intake (for vitamin D and calcium) or the Estimated Average Requirement (EAR) (all other micronutrients). Statistical analyses performed Usual daily intake of each micronutrient was estimated. For nutrients with an EAR, the EAR cut-point method was used to assess the prevalence of low nutrient intakes. Mixed models were used to identify age and racial differences in usual daily intake of each nutrient. Results African-American girls consumed less vitamin A and D, calcium, and magnesium compared to white girls. Regardless of race, a substantial percentage of girls had intakes below the EAR: vitamin E (81.2% to 99.0%), magnesium (24.0% to 94.5%), folate (46.0% to 87.3%). Intakes of vitamins A, D, and C; calcium; and magnesium decreased across years. As girls aged, there was an increasing proportion with intakes below the EAR for vitamins A, C, B-6, and B-12. Conclusions Food and nutrition professionals should continue to educate adolescent girls, especially those who are African American, about the importance of a nutrient-dense diet for optimum health.