Different Growth Patterns Persist at 24 Months of Age in Formula-Fed Infants Randomized to Consume a Meat- or Dairy-Based Complementary Diet from 5 to 12 Months of Age

Abstract

Objective: To test the long-term effect on growth status at 24 months of age in formula-fed infants who were randomized to consume a meat- or dairy-based complementary diet from 5 to 12 months of age.

Study design: Observational assessments, including anthropometric, dietary, and blood biomarkers, were conducted at 24 months of age, 1 year after the intervention ended.

Results: The retention rate at 24 months of age was 84% for the meat group and 81% for the dairy group. Mean (±SD) protein intakes at 24 months of age were 4.1 ± 1.2 and 4.0 ± 1.1 g/kmeat (n = 27) and dairy (n = 26) groups, respectively, and comparable with the estimates of US population intake. At 24 months of age, weight-for-age z score did not differ significantly between groups and was similar to that at 12 months. Length-for-age z score remained significantly higher in the meat group compared with the dairy group, and the average length was 1.9 cm greater in the meat group. Weight-for-length z score also did not differ significantly between groups. Insulin-like growth factor 1 significantly increased from 12 to 24 months of age in both groups, but insulin-like growth factor-binding protein 3 and blood urea nitrogen did not change significantly from 12 to 24 months of age and were comparable between groups.

Conclusions: The protein source-induced distinctive growth patterns observed during infancy persisted at 24 months of age, suggesting a potential long-term impact of early protein quality on growth trajectories in formula-fed infants.

Trial registration: ClinicalTrials.gov: NCT02142647.

Keywords: follow-up; growth; infant; protein source.

Conflict of interest statement

No conflict of interest.

Copyright © 2018 Elsevier Inc. All rights reserved.

Figures

Figure 1.. Protein intake at 24 months of age from different sources between groups1

1Meat n=19; Dairy n=18; By independent Student t test between groups, only fish intake was different between groups and was higher in the Meat group (P = 0.04).

Figure 2:. Growth Z score at 5, 12, and 24 months for participants who completed the 24 months assessment

Repeated measure ANOVA comparing time (12 and 24 months), group (Meat and Dairy) and their interactions. Independent Student t test was used to compare between groups at 24 months. A: no significant differences pf WAZ between groups at 24 months (P=0.65) or over time (effect of time P=0.42); B: significant difference of LAZ at 24 months (P=0.01) but no change from 12 to 24 months for either groups (effect of time P=0.44); C: no significant difference between groups of WLZ at 24 months (P=0.40) or change over time (effect of time P=0.15).

Figure 2:. Growth Z score at 5, 12, and 24 months for participants who completed the 24 months assessment

Repeated measure ANOVA comparing time (12 and 24 months), group (Meat and Dairy) and their interactions. Independent Student t test was used to compare between groups at 24 months. A: no significant differences pf WAZ between groups at 24 months (P=0.65) or over time (effect of time P=0.42); B: significant difference of LAZ at 24 months (P=0.01) but no change from 12 to 24 months for either groups (effect of time P=0.44); C: no significant difference between groups of WLZ at 24 months (P=0.40) or change over time (effect of time P=0.15).