Effect of multi-micronutrient-fortified rice on cognitive performance depends on premix composition and cognitive function tested: results of an effectiveness study in Cambodian schoolchildren.

OBJECTIVE: Even though current policy is strongly focused on the crucial first '1000 days', it might be still possible to enhance cognitive function during the pre-adolescent and adolescent years by improving micronutrient status. In Cambodia, nutritional status is poor. Provision of rice fortified with micronutrients through a school meal programme (SMP) could be a cost-effective strategy to help improve health and school performance. The present study aimed to evaluate the effect of three different micronutrient-fortified rice formulations on cognitive function in Cambodian children.

SETTING: Sixteen Cambodian schools receiving SMP.

DESIGN: The FORISCA-UltraRice®+NutriRice® study was a randomized, double-blind, placebo-controlled trial. Four groups of four schools were randomly allocated to receive normal rice, UltraRice®Original, UltraRice®New or NutriRice®. Within each school, 132 children were randomly selected. Data on cognitive performance (picture completion, block design and Raven's coloured progressive matrices (RCPM)), anthropometry, parasite infestation and micronutrient status were collected before the intervention and after 6 months.

SUBJECTS: Cognitive data were available for 1796 children aged 6-16 years.

RESULTS: All cognitive scores improved after 6 months (P<0·001). Block design score improvement was significantly higher in children consuming UltraRice®Original (P=0·03) compared with the other fortified rice groups and placebo. No difference among groups was found on RCPM or picture completion scores. Stunting, parasite infestation and inflammation negatively affected the impact of the intervention.

CONCLUSIONS: Combined with other interventions, using SMP to distribute fortified rice to schoolchildren may be a cost-effective way to increase cognitive performance and thereby improve school performance and educational achievements.