Probiotics are commonly prescribed to promote a healthy gut microbiome in children. Our objective was to investigate the effects of probiotic supplementation on growth outcomes in children 0–59 months of age. We conducted a systematic review and meta-analysis which included randomized controlled trials (RCTs) that administered probiotics to children aged 0–59 months, with growth outcomes as a result. We completed a random-effects meta-analysis and calculated a pooled standardized mean difference (SMD) or relative risk (RR) and reported with a 95% confidence interval (CI). We included 79 RCTs, 54 from high-income countries (HIC), and 25 from low-and middle-income countries (LMIC). LMIC data showed that probiotics may have a small effect on weight (SMD: 0.26, 95% CI: 0.11–0.42, grade-certainty = low) and height (SMD 0.16, 95% CI: 0.06–0.25, grade-certainty = moderate). HIC data did not show any clinically meaningful effect on weight (SMD: 0.01, 95% CI: −0.04–0.05, grade-certainty = moderate), or height (SMD: −0.01, 95% CI: −0.06–0.04, grade-certainty = moderate). There was no evidence that probiotics affected the risk of adverse events. We conclude that in otherwise healthy children aged 0–59 months, probiotics may have a small but heterogenous effect on weight and height in LMIC but not in children from HIC.
- High-income countries
- Low-and middle-income countries
- Systematic review