Folate and Vitamin B12 Status in Latin America and the Caribbean: An Update.

UNLABELLED: Background: The current magnitude of folate and vitamin B12 deficiency in Latin America and the Caribbean is uncertain. OBJECTIVE: To summarize data on plasma or serum vitamin B12 and folate concentrations in Latin America and the Caribbean reported since 1990, a period that covers the era before and after the introduction of folic acid fortification. METHODS: A systematic review was conducted in 2012 and updated in 2014. Studies and surveys using biochemical biomarkers and conducted in apparently healthy individuals were identified. RESULTS: Folate deficiency in Latin America and the Caribbean appears not to be a public health problem (prevalence < 5%) after the introduction of folic acid fortification. However, there is some indication that high rates of low or marginal vitamin B12 status remain in most locations and across population groups. CONCLUSIONS: Adding vitamin B12 as a fortificant with folic acid may be the best strategy in areas where vitamin B12 deficiency is an established concern.

Zinc Deficiency in Latin America and the Caribbean.

BACKGROUND: Zinc deficiency affects multiple vital functions in the life cycle, especially growth. Limited information is available on the magnitude of zinc deficiency in Latin America and the Caribbean. OBJECTIVE: To examine the latest available information on both the prevalence of zinc deficiency and the risk of zinc deficiency in Latin America and the Caribbean. METHODS: The prevalence of zinc deficiency was identified through a systematic review looking for the latest available data on serum zinc concentrations from surveys or studies with national representativeness conducted in Latin America and the Caribbean. The risk of zinc deficiency in Latin America and the Caribbean was estimated based on dietary zinc inadequacy (according to the 2011 National Food Balance Sheets) and stunting in children under 5 years of age. RESULTS: Only four countries had available national biochemical data. Mexican, Colombian, Ecuadorian, and Guatemalan children under 6 years of age and women 12 to 49 years of age had a high prevalence of zinc deficiency (19.1% to 56.3%). The countries with the highest risk of zinc deficiency (estimated prevalence of inadequate zinc intake > 25% plus prevalence of stunting > 20%) were Belize, Bolivia, El Salvador, Guatemala, Haiti, Honduras, Nicaragua, and Saint Vincent and the Grenadines. Zinc dietary inadequacy was directly correlated with stunting (r = 0.64, p < .001). CONCLUSIONS: Prevalence data from the four available Latin America and Caribbean national surveys indicate a high prevalence of zinc deficiency in children under 6 years of age and women 12 to 49 years of age. High rates of both estimated zinc dietary inadequacy and stunting were also reported in most Latin America and Caribbean countries.

Interpretation of Serum Retinol Data From Latin America and the Caribbean.

BACKGROUND: In recent decades, the general socioeconomic situation in Latin America and the Caribbean countries has improved, and many vitamin A programs have been implemented in an attempt to reduce vitamin A deficiency in the region. OBJECTIVE: To examine vitamin A status in Latin America and the Caribbean based on serum retinol concentrations and to contrast available data published before and after 1998. METHODS: A systematic review was performed. National surveys or representative studies that reported vitamin A status were selected. RESULTS: Ten national surveys and six representative studies were identified. Data for children under 6 years of age indicate that Guatemala and Nicaragua have practically eradicated vitamin A deficiency (less than 2% prevalence of serum retinol < 20 µg/dL). In Costa Rica, Cuba, El Salvador, and Panama, the prevalence of vitamin A deficiency ranged from 2.8% to 9.4%. In Peru, Honduras, Argentina, Ecuador, and Brazil, vitamin A deficiency is a moderate public health problem (prevalence from 14.0% to 17.4%), while in Colombia, Mexico, and Haiti it is a severe public health problem (prevalence from 24.3% to 32.0%). Disadvantaged groups (indigenous people and those of Afro-Colombian descent) have the highest rates of deficiency. The prevalence of vitamin A deficiency is under 20% in school-children and adult women. When data published before and after 1998 for children under 6 years of age were compared, most Central American countries had a reduction in the prevalence of vitamin A deficiency (p < .05), whereas in South American countries, the prevalence of vitamin A deficiency increased over time (p < .05). CONCLUSIONS: The prevalence of vitamin A deficiency in children under 6 years of age has decreased in many Central American countries, but vitamin A deficiency still remains a public health problem in numerous Latin America and Caribbean countries, especially among disadvantaged and vulnerable groups. Because of issues with the accuracy of the serum retinol biomarker reflecting body stores, these results must be interpreted with caution.

Fortification of rice: technologies and nutrients.

This article provides a comprehensive review of the currently available technologies for vitamin and mineral rice fortification. It covers currently used technologies, such as coating, dusting, and the various extrusion technologies, with the main focus being on cold, warm, and hot extrusion technologies, including process flow, required facilities, and sizes of operation. The advantages and disadvantages of the various processing methods are covered, including a discussion on micronutrients with respect to their technical feasibility during processing, storage, washing, and various cooking methods and their physiological importance. The microstructure of fortified rice kernels and their properties, such as visual appearance, sensory perception, and the impact of different micronutrient formulations, are discussed. Finally, the article covers recommendations for quality control and provides a summary of clinical trials.

Less than adequate vitamin D status and intake in Latin America and the Caribbean:a problem of unknown magnitude.

BACKGROUND: The prevalence of vitamin D deficiency in Latin America and the Caribbean is unknown. OBJECTIVE: To examine the prevalence data available on vitamin D deficiency in Latin America and the Caribbean. METHODS: A systematic review was conducted in 2011. Studies using biochemical biomarkers and dietary intake estimation were included. Studies conducted in apparently healthy individuals, independently of age, latitude, skin pigmentation, and season of the year at the time of blood collection, were included. RESULTS: A total of 243 studies were identified. The final number of selected studies was 28, including two National Health Surveys (Mexico and Argentina). There are studies that report the vitamin D status of specific subgroups conducted in Argentina, Brazil, Chile, Colombia, Ecuador, Guatemala, and Mexico. However, the small sample sizes in these studies and thus the low national representativeness of the reported data do not allow for an accurate assessment of vitamin D status at the regional level. In the majority of the countries with available data, we observed that vitamin D insufficiency was classified as a mild, moderate, or severe public health problem. The only country with a nationally representative sample was Mexico, which found 24%, 10%, 8%, and 10% prevalence rates of vitamin D insufficiency (25-hydroxyvitamin D < 50 nmol/L) in preschoolers, schoolchildren, adolescents, and adults, respectively. The prevalence of vitamin D deficiency (25-hydroxyvitamin D < 20 nmol/L) was less than 1% for all groups. CONCLUSIONS: There is some indication that vitamin D insufficiency may be a public health problem in Latin America and the Caribbean, but the exact magnitude is currently unknown.

Ascorbyl palmitate enhances iron bioavailability in iron-fortified bread.

BACKGROUND: One of the strategies to control iron deficiency anemia is the fortification of food with iron. A mechanism for improving the bioavailability of iron is to add an iron absorption promoter. OBJECTIVE: The objective was to determine the effect of ascorbyl palmitate (AP) on the bioavailability of iron in fortified bread made from refined wheat flour. DESIGN: The iron bioavailability of wheat flour fortified with either ferrous sulfate alone or ferrous sulfate plus AP was studied with the use of double radio iron (55Fe and 59Fe) erythrocyte incorporation in 14 women. RESULTS: Geometric mean (+/- range of 1 SD) iron absorption from the bread fortified with ferrous sulfate was 10.5% (4.1-27.0%). The addition of AP at molar ratios of AP to Fe of 2:1 and 4:1 significantly increased iron absorption [14.6% (5.9-36.1%) and 20.2% (10.6-38.6%), respectively; P < 0.001]. CONCLUSION: AP is a strong promoter of iron absorption from fortified bread because of its thermoresistant properties.

Enhancing the absorption of fortification iron. A SUSTAIN Task Force report.

Iron deficiency remains a major global health problem affecting an estimated 2 billion people. The World Health Organization ranked it as the seventh most important preventable risk for disease, disability, and death in 2002. Since an important factor in its causation is the poor bioavailability of iron in the cereal-based diets of many developing countries, SUSTAIN set up a Task Force, consisting of nutritional, medical, industry, and government experts to consider strategies for enhancing the absorption of fortification iron. This paper summarizes the findings of this Task Force. Detailed reviews of each strategy follow this overview. Highly soluble compounds of iron like ferrous sulfate are desirable food fortificants but cannot be used in many food vehicles because of sensory issues. Thus, potentially less well-absorbed forms of iron commonly are used in food fortification. The bioavailability of iron fortificants can, however, be enhanced with innovative ingredient technologies. Ascorbic acid, NaFeEDTA, ferrous bisglycinate, and dephytinization all enhance the absorption of fortification iron, but add to the overall costs of fortification. While all strategies cannot be recommended for all food fortification vehicles, individual strategies can be recommended for specific foods. For example, the addition of ascorbic acid is appropriate for dry blended foods such as infant foods and other dry products made for reconstitution that are packaged, stored, and prepared in a way that maximizes retention of this vitamin. NaFeEDTA can be recommended for fortification of fish sauce and soy sauce, whereas amino acid chelates may be more useful in milk products and beverages. With further development, dephytinization may be possible for low-cost, cereal-based complementary foods in developing countries. Encapsulation of iron salts in lipid coatings, while not an iron absorption-enhancing strategy per se, can prevent soluble forms of iron from interacting undesirably with some food vehicles and hence broaden the application of some fortificants. Research relevant to each of these strategies for enhancing the bioavailability or utility of iron food fortificants is reviewed. Individual strategies are evaluated in terms of enhancing effect and stability, organoleptic qualities, cost, and regulatory issues of interest to the nutrition community, industry, and consumers. Recommendations are made on potential usages and further research needs. Effective fortification depends on the selection of technically feasible and efficacious strategies. Once suitable strategies have been identified, cost becomes very important in selecting the best approach to implement. However it is essential to calculate cost in relation to the amount of bioavailable iron delivered. An approach to the calculation of cost using a conservative estimate of the enhancing effects of the innovative technologies discussed in the supplement is given in the final section.

Enhancers of iron absorption: ascorbic acid and other organic acids.

Ascorbic acid (AA), with its reducing and chelating properties, is the most efficient enhancer of non-heme iron absorption when its stability in the food vehicle is ensured. The number of studies investigating the effect of AA on ferrous sulfate absorption far outweighs that of other iron fortificants. The promotion of iron absorption in the presence of AA is more pronounced in meals containing inhibitors of iron absorption. Meals containing low to medium levels of inhibitors require the addition of AA at a molar ratio of 2:1 (e.g., 20 mg AA: 3 mg iron). To promote absorption in the presence of high levels of inhibitors, AA needs to be added at a molar ratio in excess of 4:1, which may be impractical. The effectiveness of AA in promoting absorption from less soluble compounds, such as ferrous fumarate and elemental iron, requires further investigation. The instability of AA during food processing, storage, and cooking, and the possibility of unwanted sensory changes limits the number of suitable food vehicles for AA, whether used as vitamin fortificant or as an iron enhancer. Suitable vehicles include dry-blended foods, such as complementary, precooked cereal-based infant foods, powdered milk, and other dry beverage products made for reconstitution that are packaged, stored, and prepared in a way that maximizes retention of this vitamin. The consumption of natural sources of Vitamin C (fruits and vegetables) with iron-fortified dry blended foods is also recommended. Encapsulation can mitigate some of the AA losses during processing and storage, but these interventions will also add cost. In addition, the bioavailability of encapsulated iron in the presence/absence of AA will need careful assessment in human clinical trials. The long-term effect of high AA intake on iron status may be less than predicted from single meal studies. The hypothesis that an overall increase of dietary AA intake, or fortification of some foods commonly consumed with the main meal with AA alone, may be as effective as the fortification of the same food vehicle with AA and iron, merits further investigation. This must involve the consideration of practicalities of implementation. To date, programs based on iron and AA fortification of infant formulas and cow's milk provide the strongest evidence for the efficacy of AA fortification. Present results suggest that the effect of organic acids, as measured by in vitro and in vivo methods, is dependent on the source of iron, the type and concentration of organic acid, pH, processing methods, and the food matrix. The iron absorption-enhancing effect of AA is more potent than that of other organic acids due to its ability to reduce ferric to ferrous iron. Based on the limited data available, other organic acids may only be effective at ratios of acid to iron in excess of 100 molar. This would translate into the minimum presence/addition of 1 g citric acid to a meal containing 3 mg iron. Further characterization of the effectiveness of various organic acids in promoting iron absorption is required, in particular with respect to the optimal molar ratio of organic acid to iron, and associated feasibility for food application purposes. The suggested amount of any organic acid required to produce a nutritional benefit will result in unwanted organoleptic changes in most foods, thus limiting its application to a small number of food vehicles (e.g., condiments, beverages). However, fermented foods that already contain high levels of organic acid may be suitable iron fortification vehicles.

Adequate dosing of micronutrients for different age groups in the life cycle.

Many studies of micronutrient supplementation in developing countries have used single-nutrient supplements with either vitamins or minerals. However, people in these countries often suffer from multiple, rather than single, micronutrient deficiencies. The objective of this paper is to discuss the factors that go into determining the adequate dosing of vitamins and/or minerals for people of different ages. To elaborate on the adequacy of micronutrient doses in supplements, a model described by the US FNB was used, which calculates the difference between the mean observed intake for an individual and the estimated average requirement for a life stage and gender group. This model allows estimating the degree of confidence that a certain nutrient intake (from supplements and diet) is adequate. The US/Canadian DRI values have been used as the basis for these calculations, from which it can be concluded that a daily supplement of one RDA of each micronutrient is adequate to cover the personal requirements of all individuals in each respective age and gender group of the population, provided that 20 to 40% of an RDA is supplied by the diet--likely a realistic value for developing countries. DRI values vary significantly between different age groups, reflecting changing needs over a life cycle. With the objective of a supplement to be adequate and safe, the design of a one-for-all supplement covering all age groups is not realistic. Such a supplement would either underscore or surpass the required intake of some of the age groups. Additionally the dosage of certain micronutrients might exceed the upper level of intake for lower age groups. Therefore, it is suggested that three different supplements following the one RDA concept for all micronutrients be developed for research use in developing countries for the following age groups; 1 to 3 years, 4 to 13 years, and females > 14 years (excluding during pregnancy).