Does weaning influence growth and health up to 18 months?

Area of Science:

• Pediatric Nutrition
• Infant Growth and Development
• Public Health Recommendations

Background:

• Current infant feeding guidelines lack robust evidence regarding optimal timing for solid food introduction (weaning).
• Limited data exists on the short- and medium-term health and growth consequences of early versus late weaning.

Purpose of the Study:

• To investigate the impact of weaning timing (≤12 weeks vs. >12 weeks) on infant growth and health outcomes.
• To analyze effects across different infant groups: term appropriate for gestational age (AGA), term small for gestational age (SGA), and preterm infants.
• To assess outcomes up to 18 months post-term, including growth, diarrhea, vomiting, respiratory infections, atopy, and sleep patterns.

Main Methods:

• Analysis of data from over 1600 infants across five prospective randomized trials in the UK (1993-1997).
• Comparison of infants weaned at or before 12 weeks versus those weaned after 12 weeks.
• Inclusion of term AGA, term SGA, and preterm infants.

Main Results:

• Infants weaned at ≤12 weeks were heavier at 12 weeks but exhibited slower growth in weight, length, and head circumference between 12 weeks and 18 months compared to later-weaned infants.
• By 18 months, no significant size differences were observed between early and late weaned groups in term or preterm infants.
• Breastfed term infants weaned before 12 weeks were more likely to sleep through the night at 9 months; no significant effects on other health outcomes were noted.

Conclusions:

• Weaning timing (before or after 12 weeks) showed minimal influence on infant health outcomes up to 18 months.
• While early weaning led to transient size differences, growth trajectories converged by 18 months.
• The study does not rule out potential long-term programmed effects of early or late weaning practices.