Friday, December 28, 2007

Longitudinal assessment of micronutrient intake among African American and White girls: the National Heart; Lung; and Blood Institute Growth and Healt

Prospective, epidemiologic research has shown that a healthful dietary stencil providing sufficient nutrients can reduce the risk of some cancer, CVD, and conditions such as osteoporosis. Eating patterns that influence nutrient intake are established untimely in energy. Many of the previous studies examining micronutrient intake among children have be based on cross-sectional information documenting intake only for a single light of day. Youth in the United States are promising to report low intakes of calcium; folate, magnesium, zinc and vitamins A and D. Low micronutrient intakes may be linked to long-term form risks, especially among African American girls who are at particular risk for developing CVD risk factor such as hypertension. For example, the combination of nutrients (calcium, magnesium, potassium) in the Dietary Approaches to Stop Hypertension diet may be an important factor surrounded by blood pressure reduction, and folate may own beneficial effects on blood pressure, as well.


Capitalizing on the availability of 3-day food intake background collected as part of the National Heart, Lung, and Blood Institute Growth and Health Study (NGHS), the researchers of this study examined micronutrient intake in a sizeable sample of African American and white girls from childhood through youth. In addition, they updated analyses by using the most current Dietary Reference Intakes (DRIs), which allow the comparison of intakes to the Estimated Average Requirements (EARs) as well as to the Recommended Dietary Allowances (RDAs).


The NGHS was designed to means the development of plumpness and CVD risk factors (including dietary, psychosocial, environmental, and other factors) in 2,379 African American and white females over a 10-year spell. Participants, aged 9 or 10 years at study entry, identified themselves (using census category for race/ethnicity) as "black" or "white" non-Hispanic, with racially concordant parents or guardians. Girls be recruited at three study sites: the University of California at Berkeley, Berkeley, CA; the University of Cincinnati/Cincinnati Children's Hospital Medical Center, Cincinnati, OH; and the Westat, Inc/Group Health Association, Rockville, MD. Each girl be interviewed in 10 approximately annual study years (henceforth referred to as "Years"). Retention rates were utmost in Year 2 through Year 4 (96%, 94%, and 91%, respectively), decline to a low of 82% at Year 7 and increased to 89% at Year 10.


Three-day food records that have been previously validate were collected during Years 1 through 5 and Years 7, 8, and 10; the miserable [+ or -] standard deviation age at last birthday for girls near complete food diaries in these years be 9.5 [+ or -] 0.5, 10.5 [+ or -] 0.6, 11.5 [+ or -] 0.6, 12.5 [+ or -] 0.6, 13.5 [+ or -] 0.6, 15.5 [+ or -] 0.6, 16.5 [+ or -] 0.6, and 17.9 [+ or -] 0.2 years, respectively. Girls were instructed to diary all food and drink for 3 consecutive days (2 weekdays and 1 weekend day). Beginning at Year 5, girls be asked to record the type and amount of supplements consumed, if any; past Year 5, there be no specific instructions to document supplement intake.


DRIs are nutrient reference standards that can be used for assessing and planning diets for on form people. They are established considering the role of nutrients in long-term vigour. DRIs encompass four reference values: EAR, RDA, Adequate Intake (AI), and Tolerable Upper Intake plane. For a specified indicator of adequacy, the EAR represents the nutrient intake estimated to come upon the requirement of half the in good health people contained by a particular go stage and sex group. The EAR is used to calculate the RDA. The RDA, the average on a daily basis intake level explicitly sufficient to meet the nutrient requirement of nearly adjectives healthy individuals, is intended to be a guide for the day by day intake of an individual. If sufficient data are not available to divide an EAR and set an RDA, the AI is provided for the nutrient. The AI represents a recommended daily intake even based on an observed or experimentally determined approximation of nutrient intake for a group (or groups) of fighting fit people specifically assumed to be adequate.


African American girls consumed smaller amount vitamin A and D, calcium, and magnesium compared to white girls. Regardless of race, a substantial percentage of girls have 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, nearby was an increasing proportion next to intakes below the EAR for vitamins A, C, B-6, and B-12.


The researchers evaluated micronutrient intake relative to the DRIs in a large taster of African American and white girls (ages 9 to 18 years). Overall, white girls tended to consume greater amounts of micronutrients compared to African American girls, next to the exception of vitamins E and C, and zinc. For all girls, intake of vitamins A, D, and C; calcium; and magnesium tend to decrease across the years; however, the rate of shrinking for vitamin D, calcium, and magnesium was greater among African American girls. Moreover, at hand were tribal differences in intake trends over time for vitamins E, B-6, and B-12; folate; and zinc; which typically increased for white girls but remained stable or decrease in African American girls. Improving the diet to come across the nutrient reference standards may be an efficient approach for reducing CVD risk, especially among African American girls. Regardless of race, these findings are of concern about the intake levels of several micronutrients. A substantial proportion of girls have intakes of vitamin E and magnesium that were ably below the EAR. These findings also agree with former research that has shown that a significant percentage of womanly adolescents report low intake of folate.


Using the EAR cut-point method, the researchers found that a substantial percentage of African American and white adolescent girls consumed less than the current hint values for vitamin E, magnesium, folate, and calcium. Trends noted in micronutrient consumption cannot be attributed to changes within EI, as all longitudinal models be adjusted for total activeness. Rather, these results imply that as girls aged, the nutrient density of their diet decrease, and this tendency be more pronounced among African-American girls. Food and nutrition professionals should focus their counseling efforts on on the way diets of young girls, principally those who are African American.

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