We studied hematologic findings in 617 apparently healthy Georgia elementary, middle, and high school students, aged 10 to 19 years, and examined the influence of several parameters (race, sex, iron status, and genetic hemoglobin [Hb] abnormalities) on hypochromia and microcytosis, with or without anemia. Fourteen students (2%) (6 male, 8 female; 4 white, 10 black) were found to be anemic (Hb < 11.8 g/dL in boys or < 11.3 g/dL in girls). Hypochromia (mean corpuscular Hb < 25 pg) with or without microcytosis (mean corpuscular volume < 78 fL) was found in 26 students (4%). Iron deficiency was the main associated factor in white students, but in blacks genetic Hb abnormalities, especially alpha-thalassemia trait, were other predisposing factors. The overall prevalence of iron deficiency (serum ferritin < or = 12 ng/mL) was 32.4% in the entire sample population, 30.5%, among blacks, and 33.2% among whites.