Evidence of Effectiveness of Flour Fortification on Iron Status and Anemia: A Literature Review
Helena Pachon *
Flour Fortification Initiative, Atlanta, USA.
Rebecca Spohrer
Global Alliance for Improved Nutrition, Geneva, Switzerland.
Zuguo Mei
Centers for Disease Control and Prevention, Atlanta, USA.
Mary Serdula
Centers for Disease Control and Prevention, Atlanta, USA.
*Author to whom correspondence should be addressed.
Abstract
Objectives: The effectiveness of wheat- and maize-flour fortification for improving iron status and anemia in real-world situations has not been documented. The objective was to review published and grey literature on the public-health impact of flour fortification.
Methods: A systematic literature review was undertaken, including a search of 17 databases and an e-mail appeal for unpublished reports. Two researchers reviewed 1881 documents. Only studies on government-supported, large-scale fortification programs with anemia or iron outcomes measured prior to and > 12 months after initiation of fortification were included.
Results: Twelve studies describing 25 sub-groups (n=13 for children < 15 years, n=12 for women of reproductive age (WRA)) were analyzed. Eight studies used a pre-post design, 4 included a control population, and none adjusted for possible confounding factors. From the pre- to the post-fortification periods (and as difference-in-difference for those that included a control group), hemoglobin increased significantly in 4 of 11 studies with children and 5/11 studies with WRA; hemoglobin decreased significantly in 1/11 studies with children and 2/11 with WRA. Anemia prevalence decreased significantly in 4/8 studies with children and 3/10 studies with WRA; anemia prevalence increased significantly in 1/8 studies with children and 2/3 studies with WRA. The prevalence of low serum ferritin statistically decreased in 1/6 studies with children and 3/3 studies with WRA.
Conclusions: Available studies confirm that large-scale fortification can positively impact iron and anemia status in children and women of reproductive age; however there is not enough evidence yet to understand under what conditions such impact is greatest.