IPD meta-analysis shows no effect of LC-PUFA supplementation on infant growth at 18 months

Aim: Clinical trials on the effects of long-chain polyunsaturated fatty acids (LC-PUFA) supplementation of formula milk on growth of term and preterm children have shown conflicting results. We examined the effects of LC-PUFAs - especially docosahexaenoic acid (DHA) and arachidonic acid (AA) - on growth at 18 months. Methods: We performed a meta-analysis based on individual patient data (IPD) of 901 children from four large, randomised clinical trials of formula milk with and without LC-PUFAs. Anthropometrics were assessed by z-scores based on weight for age, length for age, head circumference for age and body mass index (BMI) for age at 18 months. The studies differed in LC-PUFA composition and infant characteristics (two studies on preterm children, two on term children). Results: Multivariate regression analyses including the possible confounders, sex, gestational age, birth weight, smoking in the last trimester and maternal age, as well as interaction terms showed no significant effects of LC-PUFA supplementation on any z-score. Subgroup analyses on trials with high amounts of DHA and on studies with duration of supplementation of at least 6 months yielded the same result. These findings cannot be explained by the lack of power. Conclusion: Our IPD meta-analysis shows no evidence that LC-PUFA supplementation affects children's growth at 18 months of age.