Impact of a modified version of baby-led weaning on iron intake and status: a randomised controlled trial

OBJECTIVE: To determine the iron intake and status of infants following a version of baby-led weaning (BLW) modified to prevent iron deficiency (Baby-Led Introduction to SolidS; BLISS) compared with those of infants following traditional spoon-feeding. DESIGN, PARTICIPANTS AND INTERVENTION: This randomised controlled trial included 206 participants assigned to control (n=101) or BLISS (n=105) groups. Both groups received standard midwifery and ‘Well Child’ care. BLISS participants received eight additional visits (from before birth to 9 months) providing education and support on the BLISS approach to complementary feeding (ie, BLW modified to increase iron intake). The primary outcome of the BLISS study (growth) has been previously reported. This paper reports the key prespecified secondary outcomes, iron intake and iron status. OUTCOME MEASURES: Intake of iron and key absorption modifiers were assessed using weighed 3-day diet records at 7 and 12 months. A venipuncture blood sample was collected at 12 months to determine plasma ferritin, haemoglobin, soluble transferrin receptor, C-reactive protein and α(1)-acid glycoprotein concentrations; and body iron was calculated. RESULTS: Differences in median dietary iron intakes between the control and BLISS groups were not significant at 7 (difference 0.6 mg/day; 95% CI −1.0 to 2.3) or 12 (−0.1 mg/day; −1.6 to 1.4) months of age. Similarly, there were no significant differences in plasma ferritin concentration (difference −2.6 µg/L; 95% CI −10.9 to 5.8), body iron (0.04 mg/kg; −1.1 to 1.2) or the prevalence of depleted iron stores, early functional iron deficiency or iron deficiency anaemia (all p≥0.65) at 12 months of age. CONCLUSIONS: A baby-led approach to complementary feeding does not appear to increase the risk of iron deficiency in infants when their parents are given advice to offer ‘high-iron’ foods with each meal. TRIAL REGISTRATION NUMBER: ACTRN12612001133820; Pre-results.