Zinc and iron deficiency and their interrelations in low-income African American and Hispanic children in Atlanta

Abstract

Background: Information about the zinc status of low-income minority children in the United States is lacking.

Objective: The objective was to determine the prevalence of zinc deficiency and anemia and their interrelation among low-income African American and Hispanic preschool children.

Design: This was a cross-sectional study in which a prospective 3-d food diary was completed, and hemoglobin, serum ferritin, zinc, copper, and C-reactive protein concentrations were measured. Children with elevated C-reactive protein concentrations were excluded from analysis.

Results: Of 292 children recruited, 280 (mean +/- SD age: 2.5 +/- 1.2 y) qualified for analysis. One hundred forty-six (52%) children were African American and 134 (48%) were Hispanic; 202 (72%) were enrolled in the Women, Infants, and Children nutrition program. A low serum zinc concentration (<10.7 mumol/L) was present in 34 (12%) children, and 37 (13%) were anemic (hemoglobin < 110 g/L). African American (odds ratio: 3.47; 95% CI: 1.51, 7.96) and anemic (odds ratio: 2.92; 95% CI: 1.24, 6.90) children had an increased risk of zinc deficiency. Serum zinc correlated with hemoglobin (r = 0.24, P < 0.001). Children with a height/length less than the fifth percentile had significantly lower mean serum zinc concentrations than those with a height/length greater than the fifth percentile (12.4 +/- 1.8 compared with 13.0 +/- 2.2 micromol/L; P < 0.001). In a multiple logistic regression model, African American race-ethnicity was associated with zinc deficiency (odds ratio: 0.26; P = 0.02). The main sources of iron and zinc in the diets were meat products and cereals.

Conclusions: The prevalence of zinc deficiency and anemia was high in this population of low-income minority children, especially among African Americans. Further investigation of the incidence of zinc deficiency and the ability of anemia to screen for it is warranted.