CanImprovedLegumeVarietiesOptimizeIron StatusinLow-andMiddle-IncomeCountries?A SystematicReview

Abstract

Iron and zinc deficiencies are some of the most widespread micronutrient deficiencies in low- and middle-income countries (LMIC). Dietary diversification, food fortification, nutrition education, and supplementation can be used to control micronutrient deficiencies. Legumes are importantstaplefoodsinmosthouseholdsinLMIC.Legumesarehighlynutritious(goodsourcesofessentialminerals,fiber,andlowglycemicindex) and offer potential benefits in addressing nutrition insecurity in LMIC. Several efforts have been made to increase micronutrient intake by use of improvedlegumes.Improvedlegumeshaveahighernutrientbioavailability,lowerphytate,orreducedhard-to-cook(HTC)defect.Wehypothesize that consumption of improved legumes leads to optimization of zinc and iron status and associated health outcomes. Therefore, the objective of this review is to examine the evidence on the efficacy of interventions using improved legumes. Nine relevant studies are included in the review. Consumption of improved legumes resulted in a≥1.5-fold increase in iron intake. Several studies noted modest improvements in biomarkers of ironstatus[hemoglobin(Hb),serumferritin(SF),andtransferrinreceptor]associatedwithconsumptionofimprovedlegumes.Currently,noefficacy studies assessing the relation between consumption of improved legumes and zinc status are available in the literature. Evidence shows that, in additiontorepletionofbiomarkersofironstatus,consumptionofimprovedlegumesisassociatedwithbothclinicalandfunctionaloutcomes.The prevalenceofirondeficiency(ID)decreaseswithconsumptionofimprovedlegumes,withincreasesof≤3.0g/LinHbconcentrations.Improvement incognitionandbrainfunctioninwomenhasbeenreportedaswell.However,furtherresearchisnecessaryinmoreat-riskgroupsandalsotoshow if the reported improvements in status markers translate to improved health outcomes. Evidence from the included studies shows potential from consumptionofimprovedlegumessuggestingthemtobeasustainablesolutiontoimproveironstatus