Fractional iron absorption (%) (A) and total iron absorption (mg) (B) in Kenyan infants (n = 25) from maize porridge containing a mixture of 1.5 mg iron as⁵⁴Fe-labeled FeSO₄; as⁵⁸Fe-labeled FeSO₄+ 1.41 g apo-lactoferrin; and as intrinsically⁵⁷Fe-labeled holo-lactoferrin containing 1.41 g lactoferrin. The horizontal lines show the geometric means, and the whiskers extend from –SD to +SD. Data analyzed with repeated-measures analysis of covariance with Bonferroni post hoc analysis. Geometric means without a common letter differ, P < .05. FeSO₄, ferrous sulfate; Lf, lactoferrin. Adapted from Mikulic et al.²⁶