Symposium Report: Effective and Safe Micronutrient Interventions, Weighing the Risks against the Benefits.

Micronutrient fortification of staple foods can be an effective strategy to combat micronutrient malnutrition. When planning on fortification, challenges faced include the collection of essential information on population food and nutrient intake patterns, as well as the use of this information in a method to select appropriate fortification levels. A symposium was organized aimed at discussing the existing approaches to set effective and safe micronutrient fortification levels and to outline the challenges and needs in this area. Two different approaches to establish effective and safe fortification levels for food fortification were presented. In the first approach, the Estimated Average Requirement (EAR) and Tolerable Upper Intake Level (UL) are used as cut-points in the micronutrient intake distribution to evaluate and simulate effective and safe micronutrient intakes. This was exemplified by challenges encountered in Guatemala and Cameroon towards unequal vitamin A intake distribution and the impact of the food vehicle choice. Secondly, the risk-benefit approach was presented as an approach in which risks and benefits of micronutrient intakes can be quantified and balanced in order to optimize fortification benefits with the least risks and to allow decision making. This was illustrated by a case on folic acid fortification in The Netherlands. Irrespective of the approach, food and nutrient intake data are required to identify potential vehicles for fortification, quantify the nutrient gap to be addressed, and set the appropriate level of fortification based on consumption pattern. Such information is rarely available to the quality and extent ideal to set fortification levels and requires regular updating, as exemplified in the case of sugar fortification in Guatemala. While the EAR cut-point method can be used to determine the proportion of the population meeting their required and safe nutrient intakes and set goals, riskbenefit assessment may offer an answer to commonly-asked questions as to whether, and at which levels, the benefits of increasing micronutrient intakes outweigh the risks.

An Economic Model for Optimizing Effective Coverage of MN interventions: A Case Study of Cameroon.

Objectives: Micronutrient (MN) interventions are generally undertaken at national scale. New spatially disaggregated data on MN deficiencies in Cameroon suggest that subnational strategies may be more efficient, but methods to choose among alternative interventions are needed. We developed a tool to plan and manage sub-national MN interventions for Cameroon. Methods: Data from a nationally representative multi-stage cluster survey were used to determine the spatial distribution of MN deficiencies among population sub-groups at greatest risk. Macroregion-specific data (North, South, Douala/Yaoundé) on food intake were used to predict the effects of alternative MN intervention strategies on the prevalence of inadequate MN intake and absorption. MN supplements, fortified and biofortified foods, deworming and behavioral change communication to promote breastfeeding are among the interventions examined. Costs of alternative interventions were prepared. The costs and nutritional benefits of alternative interventions are included in an economic optimization model that chooses the best combination of MN interventions to ensure adequate MN intake, at regional level, over a ten-year planning horizon, given funding and other constraints. Results: Preliminary results indicate large spatial differences in MN deficiencies, e.g., estimated prevalence of vitamin A deficiency varied from ~62% (North region) to ~22% (Northwest region). Consumption of VA-rich foods and fortifiable foods also varies spatially. Hence, program efficiency may be enhanced by adopting targeted sub-national MN intervention strategies. Conclusions: Given spatial patterns in MN deficiencies, diet-driven effectiveness of alternative MN interventions, and costs of these interventions, sub-national MN interventions may offer efficiency gains that exceed the costs of planning and implementing them.

Vitamin A and Iron Status of Women and Young Children in Major Cities of Cameroon before and after Vitamin A Fortification of Vegetable Oil and Iron Fortification of Wheat Flour.

Objectives: Few data are available on the effectiveness of large-scale food fortification programs. We conducted representative surveys 2 y before and 1 y after introduction of vitamin A (VA)- fortified cooking oil and iron-fortified wheat flour to assess program impact on VA and iron status in urban Cameroon. Methods: In each survey, 10 different households were selected within each of the same 30 clusters in Douala and Yaoundé (n=~300/survey). Indicators of VA (retinol-binding protein, pRBP) and iron (ferritin; soluble transferrin receptor, sTfR) status, adjusted for presence of inflammation (CRP, AGP) and malaria, were assessed among women 15-49 y and children 12-59 mo. Staple food intake was measured by 1-week FFQ, and post-fortification oil and flour samples were collected. Results: Oil and flour were each consumed by >80% of participants. Post-fortification, 44% of oil (85% of "branded" oil) and 76% of flour samples were fortified. Controlling for inflammation and malaria, there was no change in pRBP between pre- and post-fortification values among women (1.41 to 1.40 μmol/L) and children (0.87 to 0.88 μmol/L), but ferritin increased (women: 37 to 47 μg/L; children: 39 to 51 μg/L, both P < 0.05) and sTfR decreased (7.7 to 6.2 and 10.6 to 8.2 mg/L, P < 0.01). Prevalence of anemia decreased among women (46 to 38%, P < 0.05) but not children. Conclusions: After 1 year of a national program, adequately-fortified products are available. Iron status indicators have increased since the initial survey; plausibility analyses will determine whether these changes are attributable to the fortification program.

Consumption of Red Palm Oil and Relationships with Vitamin A Status, Region, and Household Characteristics in a National Survey of Women and Young Children in Cameroon.

Objectives: Red palm oil (RPO) is an important plant source of vitamin A (VA) in Cameroon, where ~210,000 tons were produced in 2011. We conducted a national survey of children and women to assess the prevalence of VA deficiency, frequency and amount of RPO consumption and factors associated with RPO consumption. Methods: 1002 households, each with a child 12-59 mo and a woman 15-49 y, were enrolled in a nationally-representative cluster survey with 3 strata (North, South, Cities). VA status was assessed by inflammation-adjusted plasma retinol-binding protein (RBP). RPO consumption was measured by FFQ and 24 h recall. Results: 35% of children had low adjusted RBP. 54.9% of children and 57.8% of women consumed RPO the previous week, with a mean frequency of 12.2 times/week and 8.7 times /week among consumers, respectively. Median RPO consumption (among consumers) on the previous day was 10.7 g/d for children and 21.4 g/d for women, contributing ~1/3 of total VA intake nationally. RPO consumption was greater among women and children in the South compared with the North and Cities, but did not vary by socio-economic group. Weekly frequency of RPO intake was positively correlated with adjusted RBP among women and children nationally; however, at the regional level, the relationship was significant only among women in the South. Conclusions: Promoting RPO consumption is a potential strategy to increase VA intakes in Cameroon without increasing the risk of excessive intake. Formative research is needed to understand barriers to RPO consumption.

Predicted Impact of Large-scale Fortification on Adequacy of Vitamin A Intakes among Women and Young Children in Cameroon: Simulations Using Nationally-representative 24-h Recall Data.

Objectives: WHO recommends using information on dietary intakes to design food fortification programs, but nationally-representative, individual dietary data are rarely available in low-income countries. Prior to initiating a fortification program in Cameroon, we assessed intakes of vitamin A (VA) and fortifiable foods (vegetable oil, sugar, wheat flour, and bouillon cube), to simulate the effects of fortification with different foods and VA levels on VA intakes. Methods: In a nationally-representative, cluster survey with 3 strata (North, South, Cities), we conducted 24-h dietary recalls among 912 women 15-49 y and 883 children 12-59 mo (with duplicates in a subset). Results: Among women, 50% had usual VA intakes < 500 μg RAE/d (17% South, 99% North, 44% Cities); 58% of non-breastfeeding children had VA intake < 210 μg RAE/d (41% South, 86% North, 60% Cities). Oil fortification with 12 mg VA/kg, as currently mandated, would decrease the prevalence of inadequate intakes to 33% among women and 34% among children (73% and 55% in the North region, where VA deficiency is most common). Increasing the VA in oil or fortifying a second food would further decrease the prevalence of inadequate intakes, but would also increase the prevalence of retinol intakes above the UL, mainly among children. Conclusions: The current food fortification program can be expected to improve dietary VA adequacy among women and children in Cameroon. Modifications to the program must balance the potential to further increase VA intakes with the risk of retinol intake above the UL among children.