Background: Widespread recommendations from health organisations encourage exclusive breastfeeding for six months. However the addition of other fluids or foods before six months is common practice in many countries and communities. This practice suggests perceived benefits of early supplementation or lack of awareness of the possible risks.
Objectives: To assess the benefits and harms of supplementation for full-term healthy breastfed infants and to examine the timing and type of supplementation.
Search methods: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (1 March 2011) and reference lists of all relevant retrieved papers.
Selection criteria: Randomised or quasi-randomised controlled trials in infants under six months of age comparing exclusive breastfeeding versus breastfeeding with any additional food or fluids.
Data collection and analysis: Two authors independently selected the trials; three extracted data and assessed risk of bias.
Main results: We included six trials (814 infants). Two trials in the early days after birth that reported data did not indicate that giving additional fluids was beneficial. For duration of breastfeeding, there was a significant difference favouring exclusive breastfeeding up to and including week 20 (risk ratio (RR) 1.45, 95% confidence interval (CI) 1.05 to 1.99), indicating that supplements may contribute to reducing the duration.For infant morbidity (three trials), one newborn trial found a statistically, but not clinically, significant difference in temperature at 72 hours (MD 0.10 degrees, 95% CI 0.01 to 0.19), and that serum glucose levels were higher in glucose supplemented infants in the first 24 hours, though not at 48 hours (MD -0.24mmol/l, 95% CI -0.51 to 0.03). Two trials with four- to six-month-old infants did not indicate any benefit to supplemented infants to 26 weeks nor any risks related to morbidity or weight change.None of the trials reported on the remaining primary outcomes, infant mortality or physiological jaundice.
Authors' conclusions: We were unable to fully assess the benefits or harms of supplementation or to determine the impact from timing and type of supplementation .We found no benefit to newborn infants and possible negative effects on the duration of breastfeeding from the brief use of additional water or glucose water. For infants at four to six months, we found no benefit from additional foods nor any risks related to morbidity or weight change. Future studies should examine the longer term effects on infants and mothers, though randomising infants to receive supplements without medical need may be considered unethical.We found no evidence for disagreement with the recommendation of international health associations that exclusive breastfeeding should be recommended for healthy infants for the first six months.