The Effects of Nutritional Interventions on the Cognitive Development of Preschool-Age Children: A Systematic Review

Abstract

The developing human brain requires all essential nutrients to form and to maintain its structure. Infant and child cognitive development is dependent on adequate nutrition. Children who do not receive sufficient nutrition are at high risk of exhibiting impaired cognitive skills. This systematic review aimed to examine the effects of nutritional interventions on cognitive outcomes of preschool-age children. PubMed, PsycInfo, Academic Search Complete, and Cochrane Library electronic databases were searched to identify Randomized Controlled Trials (RCTs) published after the year 2000. Studies assessing the effects of food-based, single, and multiple micronutrient interventions on the cognition of nourished and undernourished children aged 2–6 years were deemed eligible. A total of 12 trials were identified. Eight out of the twelve studies found significant positive effects on cognitive outcomes. Iron and multiple-micronutrients supplementation yield improvements in the cognitive abilities of undernourished preschool-age children. Increased fish consumption was found to have a beneficial effect in the cognitive outcomes of nourished children. On the other hand, B-vitamin, iodized salt, and guava powder interventions failed to display significant results. Findings of this review highlight the importance of adequate nutrition during preschool years, and the crucial role sufficient nutrition plays in cognitive development.

Evaluation of a Physical Activity and Multi-Micronutrient Intervention on Cognitive and Academic Performance in South African Primary Schoolchildren

“…Nevertheless, a recent study with South African primary schoolchildren aged 6-11 years has shown that micronutrient supplementation is also beneficial for cognitive performance among this age group; however, the intervention period was considerably longer with 8.5 months [42]. In the present study, the intervention was implemented over a period of 6 months, yet, as a result of school holidays, the actual intervention period was comprised of 12 weeks; however, a recent review of micronutrient supplementation interventions on cognitive performance has shown positive effects even for interventions lasting less than 3 months [22]. Previous research also revealed that long end-of-year school holidays lasting 2-3 months can reduce academic performance independently of any intervention [43].…”

“…The effect sizes on proposed outcomes from prior research were evaluated. MMNS interventions among preschoolers from marginalized communities yield small to medium-large effect sizes for inhibitory control d = 0.2 [23,38]; however, in the scarce literature on MMNS interventions for primary schoolchildren, reported effect sizes are smaller and largely inconsistent [22,38]. Research on (school-based) physical activity interventions on cognitive performance reveal similar large effect sizes, with an average reported effect size of d = 0.18 [28].…”

“…With multi-micronutrient deficiencies as a risk factor for healthy brain development, nutrition programs, including micronutrient supplementation, may have the potential to enhance or compensate for deficits in cognitive performance. A recent review that investigated the effects of nutritional interventions on cognitive development among preschoolers found that children from LMICs who were nutritionally deprived showed significant improvements after iron and MMNS in cognitive performance [22], such as expressive language, problemsolving skills, working memory, and to a lesser degree, improvements in inhibitory control. In addition, the effect of MMNS on cognitive outcomes was positive for preschoolers from low quality schools.…”

The Impact of School Meal Programs on Educational Outcomes in African Schoolchildren: A Systematic Review

“…Although the vast majority of research on malnutrition concerns children under three years of age, it is just as important to provide older children with essential nutrients as they are still developing. Undernourished children in the preschool age group who receive the micronutrient supplementation show improvements in cognitive development [ 10 ]. A second window for growth and cognitive development opens from age 5 to 19.…”

“…Food for education programs are being used to reach MDGs and SDGs [ 9 ]. School feeding programs may also provide vital micronutrients that may benefit cognitive abilities and educational outcomes [ 9 , 10 ]. The two main types of food for education programs are school feeding programs (SFP) and take-home ration (THR) programs.…”