Age of introduction of complementary foods and growth of term, low-birth-weight, breast-fed infants: a randomized intervention study in Honduras

Abstract

The optimal age at which to introduce complementary foods is a topic of considerable debate. This study was designed to evaluate this issue in a nutritionally vulnerable population in Honduras. Mothers of low-birth-weight (1500-2500 g) term (ie, small-for-gestational-age) infants were recruited in the hospital and assisted with exclusive breast-feeding during the first 4 mo. At 4 mo, mothers were randomly assigned to either continue exclusive breast-feeding to 6 mo (EBF; n = 59) or to feed complementary solid foods (jarred rice cereal, chicken, and fruit and vegetables) twice daily from 4 to 6 mo while continuing to breast-feed at their initial frequency (SF; n = 60). At 4 and 6 mo, breast milk and total energy intake were measured for a nonrandom subsample (those who could stay overnight in a central unit: 32 EBF and 31 SF). At 4 mo, breast milk intake in the subsample was not significantly different between groups (EBF: 729 +/- 135 g/d; SF: 683 +/- 151 g/d: P >0.2); from 4 to 6 mo it increased (by 28 g/d) in the EBF group but decreased (by 39 g/d) in the SF group (P < 0.005). Nonetheless, total energy intake (including solid foods) increased more from 4 to 6 mo in the SF than in the EBF group. However, there were no significant differences between groups in weight or length gain during the intervention or subsequently (6-12 mo). There was no growth advantage of complementary feeding of small-for-gestational-age, breast-fed infants between 4 and 6 mo of age.