Circulating hepcidin is lower, and intestinal iron absorption is higher in 4-week-old Th3/+ mice. Serum hepcidin (A) and intestinal iron absorption (B) were quantified in 4- and 12-week-old male (blue circles) and female (red squares) WT and Th3/+ mice. Data are mean ± SD for n = 5 mice per group and were analyzed by 3-way ANOVA. Genotype, age, and sex interaction P values are shown in each panel.