Do multiple micronutrient interventions improve child health, growth, and development?

Micronutrient deficiencies are common and often co-occur in many developing countries. Several studies have examined the benefits of providing multiple micronutrient (MMN) interventions during pregnancy and childhood, but the implications for programs remain unclear. The key objective of this review is to summarize what is known about the efficacy of MMN interventions during early childhood on functional outcomes, namely, child health, survival, growth, and development, to guide policy and identify gaps for future research. We identified review articles including meta-analyses and intervention studies that evaluated the benefits of MMN interventions (3 or more micronutrients) in children (<5 y of age) using Pubmed and EMBASE. Several controlled trials (n = 45) and meta-analyses (n = 6) have evaluated the effects of MMN interventions primarily for child morbidity, anemia, and growth. Two studies found no effects on child mortality. The findings for respiratory illness and diarrhea are mixed, although suggestive of benefit when provided as fortified foods. There is evidence from several controlled trials (>25) and 2 meta-analyses that MMN interventions improve hemoglobin concentrations and reduce anemia, but the effects were small compared to providing only iron or iron with folic acid. Two recent meta-analyses and several intervention trials also indicated that MMN interventions improve linear growth compared to providing a placebo or single nutrients. Much less is known about the effects on MMN interventions during early childhood on motor and mental development. In summary, MMN interventions may result in improved outcomes for children in settings where micronutrient deficiencies are widespread.