Double-fortified salt is efficacious in improving indicators of iron deficiency in female Indian tea pickers

Predictors of anaemia in mothers and children in Uttar Pradesh, India

OBJECTIVE

Anaemia affects more than half of Indian women and children, but the contribution of its causes remains unquantified. We examined interrelationships between Hb and nutritional, environmental, infectious and genetic determinants of anaemia in non-pregnant mothers and children in Uttar Pradesh (UP).

DESIGN

We conducted a cross-sectional survey of households in twenty-five districts of UP between October and December 2016. We collected socio-demographic data, anthropometry and venous blood in 1238 non-pregnant mothers and their children. We analysed venous blood samples for malaria, Hb, ferritin, retinol, folate, Zn, vitamin B12, C-reactive protein, α1-acid glycoprotein (AGP) and β-thalassaemia. We used path analysis to examine pathways through which predictors of anaemia were associated with Hb concentration.

SETTING

Rural and urban households in twenty-five districts of UP.

PARTICIPANTS

Mothers 18-49 years and children 6-59 months in UP.

RESULTS

A total of 36·4 % of mothers and 56·0 % of children were anaemic, and 26·7 % of women and 44·6 % of children had Fe deficiency anaemia. Ferritin was the strongest predictor of Hb (β (95 % CI) = 1·03 (0·80, 1·27) g/dL in women and 0·90 (0·68, 1·12) g/dL in children). In children only, red blood cell folate and AGP were negatively associated with Hb and retinol was positively associated with Hb.

CONCLUSIONS

Over 70 % of mothers and children with anaemia had Fe deficiency, needing urgent attention. However, several simultaneous predictors of Hb exist, including nutrient deficiencies and inflammation. The potential of Fe interventions to address anaemia may be constrained unless coexisting determinants are jointly addressed.

Fortification of condiments and seasonings with iron for preventing anaemia and improving health

BACKGROUND

Anaemia affects approximately 1.8 billion people worldwide; over 60% of anaemia cases globally are due to iron deficiency (ID). Iron deficiency and anaemia contribute to the global burden of disease and affect physical and cognitive development in children, and work productivity and economic well-being in adults. Fortification of food with iron, alone or in combination with other nutrients, is an effective intervention to control ID. Condiments and seasonings are ideal food vehicles for iron fortification in countries where they are commonly used.

OBJECTIVES

To determine the effects and safety of condiment and seasoning fortification with iron alone or iron plus other micronutrients on iron deficiency, anaemia, and health-related outcomes in the general population.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, CINAHL, and other databases up to 24 January 2023. We also searched the International clinical trials registry platform (ICTRP) for any ongoing trials.

SELECTION CRITERIA

We included randomised controlled trials (RCTs) (randomisation at individual or cluster level), non-randomised controlled trials, interrupted time series with at least three measure points both before and after intervention, and controlled before-after studies. Participants were populations of any age (including pregnant women), from any country, excluding those with critical illness or severe co-morbidities. We included interventions in which condiments or seasonings have been fortified with any combination of iron and other vitamins and minerals, irrespective of the fortification technology used.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened and assessed the eligibility of studies. Disagreements were resolved through discussion or input from a third review author. Two review authors extracted the data and assessed the risk of bias in all the included studies. We followed the methods laid out by Cochrane and used GRADE criteria for assessing certainty of the evidence.

MAIN RESULTS

Our search identified 15,902 records after removal of duplicates. We included 16 studies with 20,512 participants (18,410 participants after adjusting for clustering effects). They were all carried out in upper-middle- and lower-middle-income countries. Three studies were controlled before-after studies, one was non-randomised trial, and 12 were RCTs (including three cluster RCTs). Six studies took place in schools; seven in communities; and one each in a nursery/kindergarten, tea estate, and factory. Three studies involved only women, one study involved both women and their children, and all other studies focused on children and/or adolescents. Nine studies used salt as a vehicle for iron fortification, three used fish sauce, two used soy sauce, one used curry powder, and one a "seasoning powder". The dose of iron received by participants ranged from 4.4 mg to 55 mg/day. The sample sizes in the trials ranged from 123 to 14,398, and study durations ranged from three months to two years. Twelve RCTs contributed data for meta-analysis. Six trials compared iron-fortified condiments versus the unfortified condiment, and six trials provided data comparing iron fortification in combination with other micronutrients versus the same condiment with other micronutrients, but no added iron. In one trial, the fortificant contained micronutrients that may have affected the absorption of iron. Overall no studies were assessed as having a low risk of bias. All included studies were assessed to have a high overall risk of bias, with the most concerns being around allocation concealment, blinding, and random sequence generation. There was very high heterogeneity amongst studies in almost all examined outcomes. Condiments/seasonings fortified with iron versus unfortified condiments/seasonings We are uncertain about whether consuming condiments/seasonings fortified with iron in comparison to the same unfortified condiment reduces anaemia at the end of intervention (risk ratio (RR) 0.34, 95% confidence interval (CI) 0.18 to 0.65; 2328 participants; 4 studies; very low-certainty of evidence). We are uncertain about whether consuming iron-fortified condiments increases haemoglobin concentrations (mean difference (MD) 6.40 (g/L), 95% CI -0.62 to 13.41; 2808 participants; 5 studies; very low-certainty evidence). Fortification of condiments/seasonings with iron probably slightly reduces ID (RR 0.33, 95% CI 0.11 to 1.01; 391 participants; 2 studies; moderate-certainty evidence). We are uncertain about whether fortification with iron increases ferritin concentration (MD 14.81 (µg/L), 95% CI 5.14 to 24.48; 4459 participants; 6 studies; very low-certainty evidence). Condiments/seasonings fortified with iron plus other micronutrients versus condiments/seasonings fortified with other micronutrients except iron Consuming condiments/seasonings fortified with iron plus other micronutrients may reduce anaemia (RR 0.59, 95% CI 0.40 to 0.89; 1007 participants; 4 studies; low-certainty evidence). We are uncertain about whether fortification of condiments/seasonings with iron plus other micronutrients will improve haemoglobin concentration (MD 6.22 g/dL, 95% CI 1.60 to 10.83; 1270 participants; 5 studies; very low-certainty evidence). It may reduce ID (RR 0.36, 95% CI 0.19 to 0.69; 1154 participants; 4 studies; low-certainty evidence). We are uncertain about whether fortification with iron plus other micronutrients improves ferritin concentration (MD 10.63 µg/L, 95% CI 2.40 to 18.85; 1251 participants; 5 studies; very low -certainty evidence). Condiments/seasonings fortified with iron versus no intervention No trial reported data on this comparison. No studies reported adverse effects. Funding sources do not appear to have distorted the results in any of the assessed trials.

AUTHORS' CONCLUSIONS

We are uncertain whether consuming iron-fortified condiments/seasonings reduces anaemia, improves haemoglobin concentration, or improves ferritin concentration. It may reduce ID. Findings about ferritin should be interpreted with caution since its concentrations increase during inflammation. Consuming condiments/seasonings fortified with iron plus other micronutrients may reduce anaemia, and we are uncertain whether this will improve haemoglobin concentration or ferritin concentration. More studies are needed to determine the true effect of iron-fortified condiments/seasonings on preventing anaemia and improving health. The effects of this intervention on other health outcomes like malaria incidence, growth and development are unclear.

A Randomized Trial of Quadruple-Fortified Salt for Anemia and Birth Defects Prevention in Southern India: Protocol Design and Methods

Background

Women of reproductive age are at an increased risk of anemia and micronutrient deficiencies. Evidence supports the role of periconceptional nutrition in the development of neural tube defects (NTDs) and other pregnancy complications. Vitamin B12 deficiency is a risk factor for NTDs and may modify folate biomarkers that predict NTD risk at the population level. There is an interest in mandatory fortification with vitamin B12 and folic acid for anemia and birth defect prevention. However, there are limited population-representative data needed to inform policy and guidelines.

Objectives

This randomized trial will be conducted to evaluate the efficacy of quadruple-fortified salt (QFS; iron, iodine, folic acid, vitamin B12) in 1,000 households in Southern India.

Methods

Women 18 to 49 y who are not pregnant or lactating and reside within the catchment area of our community-based research site in Southern India will be screened and invited to participate in the trial. After informed consent, women and their households will be randomized to receive one of the following 4 interventions: 1) double-fortified salt (DFS; iron, iodine), 2) DFS + folic acid (iron, iodine, folic acid), 3) DFS + vitamin B12 (iron, iodine, vitamin B12), or 4) DFS + folic acid and vitamin B12 (QFS; iron, iodine, folic acid, vitamin B12) for 12 mo. Structured interviews will be conducted by trained nurse enumerators to collect sociodemographic, anthropometric, dietary, health, and reproductive history data. Biological samples will be collected at baseline, midpoint, and endpoint. Whole blood will be analyzed for hemoglobin using Coulter Counter. Total vitamin B12 will be measured by chemiluminescence; red blood cell folate and serum folate will be evaluated using the World Health Organization-recommended microbiologic assay.

Conclusions

The results of this randomized trial will help to evaluate the efficacy of QFS to prevent anemia and micronutrient deficiencies. Clinical trial registration numbers: NCT03853304 and Clinical Trial Registry of India REF/2019/03/024479.

Registration number

NCT03853304 and REF/2019/03/024479.

Field-friendly MUNNG® optima simple test kit for quick qualitative assessment of iodine and iron presence in double-fortified salt

Background

Data from several efficacy studies and a long-term effectiveness study have encouraged the governments to adopt a policy of providing double-fortified salt (DFS) in the Mid-Day Meal (MDM) programs in government schools across India. These envisaged food security events are likely to boost the manufacturing of DFS in a big way. Thus, it becomes pertinent to come up with a robust monitoring system involving community and field workers for quality checks. It is imperative to equip these field workers with simple testing kits (STKs) capable of qualitative detection of iron and iodine in DFS. As the consumer acceptance of foods is based on several factors including sensory characteristics, performance, convenience, cost, nutrition, and product image, a variety of iron compounds are in use for fortification. However, it becomes challenging to provide a kit that can overcome the chemical masking of iodine detection by iron compounds.

Objectives

We aimed at (1) the development of a field-friendly STK for quick qualitative assessment of iodine and various forms of iron present in DFS, (2) to check its validity under field conditions.

Methods

We put in place reagents combined using known chemical reactions and balanced use of oxidants to overcome the problems of encapsulation and to maximize the use, by enabling reagent combination to react with all forms of iron.

Results

The kit reagents successfully detect iodine as well as three commonly used iron fortificants in DFS. Published field trials confirmed the specificity and sensitivity of the developed kit. The simplicity and use of the kit by a field worker can be seen in the enclosed video.

Conclusion

The combination of improvised kit reagents allows early detection of iron and iodine in DFS. Iron is detected in a variety of iron-containing fortifications. The provision of diluted H2O2 ensures the presence of oxygen-free radicals that enhances iodine release captured by concentrated KI making iodine detection an easy task.

Multiple micronutrients fortified salt: consumers' acceptability survey, Tanzania

BACKGROUND

Food fortification with micronutrients is an insufficiently used technology in developing countries. Salt is consumed in small, constant daily amounts by most people globally. Salt has been instrumental in delivering iodine to a wide population globally through fortification. There is a proven effective technology for fortifying iodinated salt with iron, folate, and Vitamin B12. Findings have shown that both Double (Iodine and iron) fortified salt (DFS) and quadruple (iron, iodine, folate, and vitamin B12) fortified salt (QFS) are effective in raising hemoglobin levels.

AIM

To assess the acceptability and gauge consumers' willingness to use double-fortified and quadruple-fortified salt formulations.

METHODS

We conducted an observational study involving 300 households at Haydom Lutheran Hospital catchment area in Northern rural Tanzania between October 2021 and April 2022. Each household was supplied with one type of salt (iodized salt (IS), DFS or QFS) for cooking common family dishes for one week. Thereafter, at least two adult members of the family who used the dishes cooked with study salt were interviewed using the adopted 5-point Hedonic scale.

RESULTS

A total of 899 individuals were interviewed after using study salt for one week: 286 IS, 305 DFS, and 308 QFS. The overall acceptability for the salts was QFS (82%), DFS (78%), and IS (79%). The mean sensory (taste, color and appearance) scores of the QFS (1.7) and DFS (1.7) were comparable to standard iodized salt (1.6).

CONCLUSION

Quadruple-fortified salt and double-fortified salt are equally acceptable and have similar sensory scores as standard iodized salt when used to cook commonly eaten dishes in the study population.

Sensory Trial of Quintuple Fortified Salt—Salt Fortified With Iodine, Iron, Folic Acid, Vitamin B12, and Zinc—Among Consumers in New Delhi, India

Background:

Micronutrient deficiencies are a cause of significant public health burden and loss of gross domestic product, especially in developing countries. Multiple fortified salt can potentially address this challenge at scale and in a cost-effective manner.

Objective:

This laboratory-based sensory trial evaluated the acceptability of quintuple fortified salt (Q₅FS), that is, iodized salt (IS) fortified with additional 4 micronutrients: iron, folic acid, vitamin B₁₂, and zinc. Iodized salt and double fortified salt (DFS), that is, IS fortified with iron, are used for comparison.

Methods:

Forty-five respondents were recruited by open invitations to the university staff and their families. Each study participant rated 10 food items each in a set of 3 identical preparations differing only in the salt used. A 5-point hedonic scale was used to rate each dish on 6 sensory attributes: appearance, color, aroma, taste, texture, and aftertaste. Finally, the dish was rated on the attribute of overall acceptability—a subjective combined score based on all sensory attributes considered together.

Results:

Among the 3 salt types, there was no difference in scores for the sensory attributes of appearance, aroma, taste, texture, and aftertaste, and the attribute of overall acceptability. Color in IS scored significantly higher than in Q₅FS and DFS, but there was no difference between the scores of DFS and Q₅FS.

Conclusions:

The 3 salts IS, DFS, and Q₅FS are comparable to each other in all sensory properties, except for color. This study concludes that Q₅FS is organoleptically acceptable under ideal conditions.

Fortification of salt with iron and iodine versus fortification of salt with iodine alone for improving iron and iodine status

BACKGROUND

Iron deficiency is an important micronutrient deficiency contributing to the global burden of disease, and particularly affects children, premenopausal women, and people in low-resource settings. Anaemia is a possible consequence of iron deficiency, although clinical and functional manifestations of anemia can occur without iron deficiency (e.g. from other nutritional deficiencies, inflammation, and parasitic infections). Direct nutritional interventions, such as large-scale food fortification, can improve micronutrient status, especially in vulnerable populations. Given the highly successful delivery of iodine through salt iodisation, fortifying salt with iodine and iron has been proposed as a method for preventing iron deficiency anaemia. Further investigation of the effect of double-fortified salt (i.e. with iron and iodine) on iron deficiency and related outcomes is warranted.  OBJECTIVES: To assess the effect of double-fortified salt (DFS) compared to iodised salt (IS) on measures of iron and iodine status in all age groups.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, five other databases, and two trial registries up to April 2021. We also searched relevant websites, reference lists, and contacted the authors of included studies.

SELECTION CRITERIA

All prospective randomised controlled trials (RCTs), including cluster-randomised controlled trials (cRCTs), and controlled before-after (CBA) studies, comparing DFS with IS on measures of iron and iodine status were eligible, irrespective of language or publication status. Study reports published as abstracts were also eligible.

DATA COLLECTION AND ANALYSIS

Three review authors applied the study selection criteria, extracted data, and assessed risk of bias. Two review authors rated the certainty of the evidence using GRADE. When necessary, we contacted study authors for additional information. We assessed RCTs, cRCTs and CBA studies using the Cochrane RoB 1 tool and Cochrane Effective Practice and Organisation of Care (EPOC) tool across the following domains: random sequence generation; allocation concealment; blinding of participants and personnel; blinding of outcome assessment; incomplete outcome data; selective reporting; and other potential sources of bias due to similar baseline characteristics, similar baseline outcome assessments, and declarations of conflicts of interest and funding sources. We also assessed cRCTs for recruitment bias, baseline imbalance, loss of clusters, incorrect analysis, and comparability with individually randomised studies. We assigned studies an overall risk of bias judgement (low risk, high risk, or unclear).  MAIN RESULTS: We included 18 studies (7 RCTs, 7 cRCTs, 4 CBA studies), involving over 8800 individuals from five countries. One study did not contribute to analyses. All studies used IS as the comparator and measured and reported outcomes at study endpoint.  With regards to risk of bias, five RCTs had unclear risk of bias, with some concerns in random sequence generation and allocation concealment, while we assessed two RCTs to have a high risk of bias overall, whereby high risk was noted in at least one or more domain(s). Of the seven cRCTs, we assessed six at high risk of bias overall, with one or more domain(s) judged as high risk and one cRCT had an unclear risk of bias with concerns around allocation and blinding. The four CBA studies had high or unclear risk of bias for most domains. The RCT evidence suggested that, compared to IS, DFS may slightly improve haemoglobin concentration (mean difference (MD) 0.43 g/dL, 95% confidence interval (CI) 0.23 to 0.63; 13 studies, 4564 participants; low-certainty evidence), but DFS may reduce urinary iodine concentration compared to IS (MD -96.86 μg/L, 95% CI -164.99 to -28.73; 7 studies, 1594 participants; low-certainty evidence), although both salts increased mean urinary iodine concentration above the cut-off deficiency. For CBA studies, we found DFS made no difference in haemoglobin concentration (MD 0.26 g/dL, 95% CI -0.10 to 0.63; 4 studies, 1397 participants) or urinary iodine concentration (MD -17.27 µg/L, 95% CI -49.27 to 14.73; 3 studies, 1127 participants). No studies measured blood pressure. For secondary outcomes reported in RCTs, DFS may result in little to no difference in ferritin concentration (MD -3.94 µg/L, 95% CI -20.65 to 12.77; 5 studies, 1419 participants; low-certainty evidence) or transferrin receptor concentration (MD -4.68 mg/L, 95% CI -11.67 to 2.31; 5 studies, 1256 participants; low-certainty evidence) compared to IS. However, DFS may reduce zinc protoporphyrin concentration (MD -27.26 µmol/mol, 95% CI -47.49 to -7.03; 3 studies, 921 participants; low-certainty evidence) and result in a slight increase in body iron stores (MD 1.77 mg/kg, 95% CI 0.79 to 2.74; 4 studies, 847 participants; low-certainty evidence). In terms of prevalence of anaemia, DFS may reduce the risk of anaemia by 21% (risk ratio (RR) 0.79, 95% CI 0.66 to 0.94; P = 0.007; 8 studies, 2593 participants; moderate-certainty evidence). Likewise, DFS may reduce the risk of iron deficiency anaemia by 65% (RR 0.35, 95% CI 0.24 to 0.52; 5 studies, 1209 participants; low-certainty evidence).  Four studies measured salt intake at endline, although only one study reported this for both groups. Two studies reported prevalence of goitre, while one CBA study measured and reported serum iron concentration. One study reported adverse effects. No studies measured hepcidin concentration.

AUTHORS' CONCLUSIONS

Our findings suggest DFS may have a small positive impact on haemoglobin concentration and the prevalence of anaemia compared to IS, particularly when considering efficacy studies. Future research should prioritise studies that incorporate robust study designs and outcome measures (e.g. anaemia, iron status measures) to better understand the effect of DFS provision to a free-living population (non-research population), where there could be an added cost to purchase double-fortified salt. Adequately measuring salt intake, both at baseline and endline, and adjusting for inflammation will be important to understanding the true effect on measures of iron status.

Ensuring the Efficacious Iron Fortification of Foods: A Tale of Two Barriers

Iron fortification of foods has always been a challenge. This is because iron fortification compounds vary widely in relative absorption; because many foods undergo unacceptable changes in color or flavor from the addition of iron; and because many of the iron-fortified foods contain potent inhibitors of iron absorption. These technical barriers have largely been overcome, and efficacious iron-fortified foods, that maintain or improve the iron status of women or children in long-term feeding studies, can be designed. Commercially fortified infant foods are efficacious, and other commercial iron-fortified foods targeted at women and children will provide a useful amount of iron provided the fortification level is adjusted according to the relative absorption of the iron compound. Technologies for the large-scale fortification of wheat and maize flour are also well established, and iron fortification of rice, using the recently developed extruded premix technique, is showing great promise. However, some important knowledge gaps still remain, and further research and development is needed in relation to iron (and iodine)-fortified salt and iron-fortified liquid milk. The usefulness of less-soluble iron compounds, such as ferrous fumarate, to fortify foods for infants and young children in low- and middle-income countries (LMICs) also needs further investigation. A more formidable barrier to efficacious iron-fortified food has been reported in recent years. This is the infection-initiated inflammation barrier, which inhibits iron absorption in response to infection. This barrier is particularly important in LMICs where infections such as malaria and HIV are widespread, and gastrointestinal infections are common due to poor quality water supplies and sanitation. Another source of inflammation in such countries is the high prevalence of obesity in women. Most countries in sub-Saharan Africa have high inflammation which not only decreases the efficacy of iron-fortified and iron-biofortified foods but complicates the monitoring of large-scale iron fortification programs. This is because iron deficiency anemia cannot be differentiated from the more prominent anemia of inflammation and because inflammation confounds the measurement of iron status. There is an urgent need to better quantify the impact of inflammation on the efficacy of iron-fortified foods. However, at present, in LMICs with high inflammation exposure, infection control, cleaner water, improved sanitation, and a decrease in obesity prevalence will undoubtedly have a greater impact on iron status and anemia than the iron fortification of foods.

Uptake of Encapsulated Ferrous Fumarate Double Fortified Salt in the Public Distribution System in India: A Value Chain Analysis

Food fortification is a powerful strategy to reach large populations with multiple micronutrients added to a single food vehicle. The impact depends on the sustained provision and utilization of adequately fortified food by a large population (mainly in low-income and food-insecure settings). We apply a value chain (VC) analysis framework to diagnose and address the barriers to the uptake of encapsulated ferrous fumarate double fortified salt (DFS) distributed through public-sector-led DFS interventions in India.We adapt the VC requirements framework proposed by Henson and Humphrey to identify and categorize barriers along the DFS VC as technological, market-related, and policy-related. We conducted a desk review of published and unpublished literature on DFS and information available in the public domain, semi-structured interviews with VC stakeholders from the private sector, program data from implementing organizations, and participation in multistakeholder consultations on DFS.Major supply-side barriers were under-developed private markets, inconsistent demand from public markets, unpredictable returns-on-investments, and inadequate business incentives to invest in DFS. The product's weak consumer orientation, uncreated consumer demand, low awareness of fortified foods, inadequate nutrition signaling were significant demand-side barriers. Technological barriers related to the requirement of high-grade salt for DFS production and residual organoleptic property of mild discoloration of food. Policy barriers related to inadequate and irregular financing for distributing subsidized DFS through the public distribution system; insufficient policy support for risk-sharing and managing costs associated with fortification; and a weak institutional environment for sustaining DFS interventions.Building an enabling institutional environment, demand creation through consumer awareness, strengthening institutional markets through public financing, managing cost and risks through public-private partnerships, and assuring quality during commercial scale-up are critical interventions necessary to ensure impact at scale.

Plant-Based Dietary Practices and Socioeconomic Factors That Influence Anemia in India

While rates of malnutrition have declined over the last decade in India due to successful government interventions, the prevalence of anemia remains high. Staple foods provide almost 70% of the daily iron intake. As staple foods are a rich source of phytate, this ingested iron is poorly absorbed. Currently, 59% of children below 3 years of age, 50% of expectant mothers and 53% of women aged 15-19 years are anemic. The most common intervention strategy has been through the use of iron supplements. While the compliance has been low and supplies irregular, such high rates of anemia cannot be explained by iron deficiency alone. This review attempts to fit dietary and cooking practices, field-level diagnostics, cultural beliefs and constraints in implementation of management strategies into a larger picture scenario to offer insights as to why anemia continues to plague India. Since the rural Indian diet is predominantly vegetarian, we also review dietary factors that influence non-heme iron absorption. As a reference point, we also contrast anemia-related trends in India to the U.S.A. Thus, this review is an effort to convey a holistic evaluation while providing approaches to address this public health crisis.

The Impact of Double-Fortified Salt Delivered Through the Public Distribution System on Iodine Status in Women of Reproductive Age in Rural India

BACKGROUND

Double-fortified salt (DFS) with iron and iodine has been demonstrated to be efficacious but questions of unintended effects on the gains in salt iodization remain. The main cross-sectional study based on the use of DFS over 1 y showed a reduction in iron deficiency risk. Whether the programs and the levels of added iron can adversely affect iodine status is yet to be established.

OBJECTIVES

We hypothesized that the addition of iron to iodized salt can adversely affect iodine status in women of reproductive age (WRA).

METHODS

A cross-sectional substudy was conducted in 4 matched-pair adjacent districts of rural Uttar Pradesh, India, in 2019. Under the public distribution system (PDS), DFS was available for 1 y through Fair Price Shops, in the 2 DFS supply districts (DFS-SDs). In these districts, iodized salt was also available in the market. In the 2 compared DFS nonsupply districts (DFS-NSDs), only iodized salt was available. In the substudy, participants included WRA (n = 1624) residing in rural areas of the selected districts. Iodine content in urine and salt samples was measured in each of the groups.

RESULTS

Significantly fewer women from the DFS-SDs had median urinary iodine concentration values indicative of moderate to mild iodine deficiency compared with the women from the DFS-NSDs. The salt purchase pattern and iodine content revealed that significantly fewer (21.99%) households in the DFS-SDs were purchasing inadequately iodized crystal salt, compared with 36.04% households in the DFS-NSDs.

CONCLUSIONS

The data reject the working hypothesis and suggest a beneficial effect of the DFS program on the iodine status in WRA, thereby supporting a recommendation of DFS supply through the PDS.

The Potential of Iodine and Iron Double-Fortified Salt Compared with Iron-Fortified Staple Foods to Increase Population Iron Status

The potential of double-fortified salt (DFS) to improve population iron status is compared with the potential of iron-fortified wheat flour, maize flour, rice grains, and milk products. The potential for a positive impact on iron status is based on reported efficacy studies, consumption patterns, the extent of industrialization, and whether there are remaining technical issues with the fortification technologies. Efficacy studies with DFS, and with iron-fortified wheat flour, maize flour, and rice, have all reported good potential to improve population iron status. Iron-fortified milk powder has shown good impact in young children. When these foods are industrially fortified in modern, automated facilities, with high-level quality control and assurance practices, high-quality raw materials, and a wide population coverage, all vehicles have good potential to improve iron status. Relative to other fortification vehicles, fortification practices with wheat flour are the most advanced and iron-fortified wheat flour has the highest potential for impact in the short- to medium-term in countries where wheat flour is consumed as a staple. Liquid milk has the least potential, mainly because an acceptable iron fortification technology has not yet been developed. Maize is still predominantly milled in small-scale local mills and, although the extruded rice premix technology holds great promise, it is still under development. Salt has a proven record as an excellent vehicle for iodine fortification and has demonstrated good potential for iron fortification. However, technical issues remain with DFS and further studies are needed to better understand and avoid color formation and iron-catalyzed iodine losses in both high- and low-quality salts under different storage conditions. There is currently a risk that the introduction of DFS may jeopardize the success of existing salt iodization programs because the addition of iron may increase iodine losses and cause unacceptable color formation.

Can Double Fortification of Salt with Iron and Iodine Reduce Anemia, Iron Deficiency Anemia, Iron Deficiency, Iodine Deficiency, and Functional Outcomes? Evidence of Efficacy, Effectiveness, and Safety

BACKGROUND

Anemia, iron deficiency, and iodine deficiency are problems of important public health concern in many parts of the world, with consequences for the health, development, and work capacity of populations. Several countries are beginning to implement double fortified salt (DFS) programs to simultaneously address iodine and iron deficiencies.

OBJECTIVE

Our objective was to summarize the evidence for efficacy and effectiveness of DFS on the full range of status and functional outcomes and across different implementation and evaluation designs essential to successful interventions.

METHODS

We conducted a systematic review and meta-analysis of published and gray literature examining the effects of DFS on nutritional status, cognition, work productivity, development, and morbidity of all population groups. We searched for articles in Medline, Embase, CINAHL, Cochrane Central Register, and ProQuest for randomized trials, quasi-randomized trials, and program effectiveness evaluations.

RESULTS

A total of 22 studies (N individuals = 52,758) were included. Efficacy studies indicated a significant overall positive effect on hemoglobin concentration [standardized mean difference (95% CI): 0.33 (0.18, 0.48)], ferritin [0.42 (0.08, 0.76)], anemia [risk ratio (95% CI): 0.80 (0.70, 0.92)], and iron deficiency anemia [0.36 (0.24, 0.55)]. Effects on urinary iodine concentration were not significantly different between DFS and iodized salt. The impact on functional outcomes was mixed. Only 2 effectiveness studies were identified. They reported programmatic challenges including low coverage, suboptimal DFS quality, and storage constraints.

CONCLUSIONS

Given the biological benefits of DFS across several populations in efficacy research, additional evaluations of robust DFS programs delivered at scale, which consider effective implementation and measure appropriate biomarkers, are needed.

Iron status is associated with worker productivity, independent of physical effort in Indian tea estate workers

Iron deficiency is the most common nutrient deficiency in the world, affecting roughly 40% of women in nonindustrialized countries. Iron is the essential element in hemoglobin, the major carrier of blood oxygen and oxidative metabolism that supports physical and cognitive performance. The relationship between iron and physical work capacity suggests that iron deficient individuals could experience reduced work output. Participants were 138 experienced tea pluckers aged 18–55 years from the Panighatta Tea Estate in Darjeeling District of northern West Bengal, India. Hemoglobin, serum ferritin, and soluble transferrin receptor were measured from venous blood. Energy expenditure was estimated from accelerometry and heart rate, and plucking productivity was measured as amount of tea plucked during the morning work session when temperature and rainfall conditions are optimal. At a given level of energy expenditure, iron deficient, anemic, and iron deficient anemic women plucked less tea during a 3-h period. The results warrant further research as to whether interventions providing supplemental iron might improve worker productivity and work efficiency. Further study should examine evidence of economic incentives for policies and programs targeting nutritional deficiencies.

Novelty Anemia predicts up to 2.02 kg (9.1%) less tea plucked per 3 h, or 4.0% lower wage per 3 h, compared with nonanemic women, controlling for physical effort. An increase of 1.0 g/L in hemoglobin concentration predicts 0.71 kg (3.3%) more tea plucked over 3 h. An increase of 1.0 g/L in hemoglobin concentration predicts a 1.6% wage increase.

High Coverage and Low Utilization of the Double Fortified Salt Program in Uttar Pradesh, India: Implications for Program Implementation and Evaluation

BACKGROUND

Double fortified salt (DFS) is efficacious in addressing iron deficiency, but evidence of its effectiveness is limited. The few published evaluations do not include details on program implementation, limiting their utility for programmatic decisions.

OBJECTIVES

We sought to characterize the coverage of a DFS program implemented through the Public Distribution System (PDS) in Uttar Pradesh, India, and understand the drivers of DFS adherence.

METHODS

After 8 mo of implementation, we surveyed 1202 households in 5 districts and collected data on sociodemographic characteristics, asset ownership, food security, and regular PDS utilization. We defined DFS program coverage as the proportion of PDS beneficiaries who had heard of and purchased DFS, and we defined DFS adherence as DFS use reported by households. We used principal component analysis to create an asset-based index of relative wealth, and we categorized households into higher/lower relative wealth quintiles. We conducted path analyses to examine the drivers of DFS adherence, particularly the mediated influence of household wealth on DFS adherence. The evaluation is registered with 3ie's Registry for International Development Impact Evaluations (RIDIE-STUDY-ID-58f6eeb45c050).

RESULTS

The DFS program had good coverage: 83% of respondents had heard of DFS and 74% had purchased it at least once. However, only 23% exclusively used DFS. Respondents had low awareness about DFS benefits and considered DFS quality as poor. Being in a lower household wealth quintile and being food insecure were significant drivers of DFS adherence, and regular PDS utilization acted as a mediator. Adherence was lower in urban areas.

CONCLUSIONS

We observed significant heterogeneity in DFS implementation as reflected by high coverage and low adherence. Findings from this process evaluation informed the design of an adaptive impact evaluation and provided generalizable insights for ensuring that the potential for impact is realized. Efforts are needed to increase awareness, improve product quality, as well as mitigate against the sensory challenges identified.

Performance Factors Influencing Efficacy and Effectiveness of Iron Fortification Programs of Condiments for Improving Anemia Prevalence and Iron Status in Populations: A Systematic Review

Iron fortification of staple foods is a common practice around the world to reduce the prevalence of iron-deficiency anemia. More recently, fortified condiments, including salts, sauces, and powders, have been tested in various efficacy trials. However, there is limited information on how nutritional, environmental, and experimental factors affect their efficacy and effectiveness. The purpose of the present work was to systematically review performance factors affecting the efficacy of condiment fortification trials. Three databases were searched using a standardized keyword search and included based on four-point inclusion criteria. Studies were evaluated against a quality assessment tool and effect sizes were calculated. Studies were ranked as low or high performing, based on whether or not they significantly improved iron-deficiency outcomes (hemoglobin, anemia prevalence, and ferritin levels). Of the 955 retrieved studies, 23 were included-of which, nine performed poorly, eight performed highly, and six were classified as neither because they did not meet the criteria of assessing the three iron outcomes. Results showed that unsuccessful trials did not consider environmental factors such as parasitic infections, nutritional factors such as micronutrient deficiencies other than iron, consumer acceptability of the product or experimental factors such as monitoring and adherence to the trials. Two common performing factors identified among those studies performing highly vs. those that did not were the control of sensory changes and monitoring of consumption compliance (i.e., dose delivery). The present work can be used as decision-making support for nutrition policy makers when determining the appropriate implementation of condiment fortification programs.

Improving the lives of millions through new double fortification of salt technology

Micronutrient deficiencies (including iodine and iron deficiency) is a global health problem affecting one third of the world's population. Salt is an ideal carrier for food fortification as it is universally consumed at equal rates, independently of economic status, and it is industrially processed. Addressing iron and iodine deficiencies together is a challenge, due to interaction between iodine and iron, negating the effect of added iodine. This paper explains the development of an improved microencapsulation‐based technology to produce iron premix, which, when added to iodized salt, is stable and organoleptically indistinguishable. Ferrous fumarate was extruded, followed by cutting, sieving to achieve a size of 300–710 μm (salt grain size). Agglomerated extrudates were microencapsulated (5% hydroxypropyl methylcellulose and 5% soy stearin) to form iron premix. Microencapsulation ensures that the added micronutrients are stable without interaction or degradation. Double Fortified Salt is formed by blending iron premix with iodized salt (1:200 ratio). This technology was transferred to India for industrial scale‐up. The public distribution system was utilized to establish and monitor an efficient distribution network for DFS in a transparent manner. The scale‐up process was initially demonstrated in the state of Uttar Pradesh, following its success two more Indian states have started distribution of DFS. At present, the DFS with iron and iodine is reaching 60 million people in India. This important health intervention technology through food fortification has the potential to be scaled globally to ensure a world free from iron deficiency anemia.

Micronutrients, iodine status and concentrations of thyroid hormones: a systematic review

Context

The metabolism of thyroid hormones, which are essential for normal development, involves many proteins and enzymes. It requires iodine as a key component but is also influenced by several other micronutrients, including selenium, zinc, iron, and vitamin A.

Objective

This systematic review was designed to investigate the effect of micronutrient status and supplementation on iodine status and thyroid hormone concentrations.

Data Sources

Using the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analysis) guidelines, electronic databases were searched from their inception to April 2016.

Study Selection

Human studies published in English and reporting data on micronutrient status and iodine status and/or thyroid hormone concentrations were included. Studies that examined the effect of micronutrient supplementation on iodine status and/or thyroid hormone concentrations were also included.

Data Extraction

A predesigned and piloted data extraction form was used to compile data from individual studies.

Results

A total of 57 studies were included: 20 intervention studies and 37 observational studies. Although observational evidence suggests that concentrations of selenium, zinc, and iron are positively associated with iodine status, data from randomized controlled trials fail to confirm this relationship.

Conclusions

Further studies are needed to provide greater understanding of the role of micronutrient status in iodine nutrition and thyroid function to ascertain the public health implications for populations worldwide.

Predicting potential to benefit from an iron intervention: a randomized controlled trial of double-fortified salt in female Indian tea pluckers

OBJECTIVE

The present study examines characteristics of those who benefited from a dietary Fe intervention comprised of salt double-fortified with iodine and Fe (DFS).

DESIGN

Data from a randomized controlled trial were analysed to identify predictors of improved Fe status and resolution of Fe deficiency (serum ferritin (sFt) < 12 μg/l) and low body Fe (body Fe (BI) < 0·0 mg/kg) using non-parametric estimations and binomial regression models.

SETTING

A tea estate in West Bengal, India.

PARTICIPANTS

Female tea pluckers, aged 18-55 years.

RESULTS

Consuming DFS significantly (P = 0·01) predicted resolution of Fe deficiency (relative risk (RR) = 2·31) and of low BI (RR = 2·78) compared with consuming iodized salt. Baseline sFt (β = -0·32 (se 0·03), P < 0·001) and treatment group (β = 0·13 (se 0·03), P < 0·001) significantly predicted change in sFt. The interaction of baseline BI with treatment group (β = -0·11 (se 0·06), P = 0·08) predicted the change in BI. DFS did not significantly predict change in Hb and marginally predicted resolution of anaemia (Hb < 120 g/l).

CONCLUSIONS

Baseline Fe status, as assessed by sFt and BI, and consumption of DFS predict change in Fe status and resolution of Fe deficiency and low BI. Anaemia prevalence and Hb level, although simple and inexpensive to measure, may not be adequate to predict resolution of Fe deficiency in response to an intervention of DFS in similar populations with high prevalence of Fe deficiency and multiple nutritional causes of anaemia. These findings will guide appropriate targeting of future interventions.

Dietary Iron Intake and Anemia Are Weakly Associated, Limiting Effective Iron Fortification Strategies in India

BACKGROUND

Anemia prevalence in India remains high despite preventive iron supplementation programs. Consequently, concurrent national policies of iron fortification of staple foods have been initiated.

OBJECTIVES

This study evaluated the relation between dietary iron intake and anemia (hemoglobin <12 g/dL) in women of reproductive age (WRA; 15-49 y) with respect to iron fortification in India.

METHODS

Data from 2 national surveys were used. Data on hemoglobin in WRA were sourced from the National Family Health Survey-4, whereas dietary intakes were sourced from the National Sample Survey. Adjusted odds for anemia with increasing iron intake were estimated, along with the effect of modulating nutrients such as vitamins B-12 and C, from statistically matched household data from the 2 surveys. The risks of inadequate (less than the Estimated Average Requirement for WRA) and excess (more than the tolerable upper limit for WRA) intakes of iron were estimated by the probability approach.

RESULTS

The relation between iron intake and the odds of anemia was weak (OR: 0.992; 95% CI: 0.991, 0.994); increasing iron intake by 10 mg/d reduced the odds of anemia by 8%. Phytate and vitamin B-12 and C intakes modified this relation by reducing the odds by 1.5% when vitamin B-12 and C intakes were set at 2 μg/d and 40 mg/d, respectively. The additional intake of 10 mg/d of fortified iron reduced the risk of dietary iron inadequacy from 24-94% to 9-39% across states, with no risk of excess iron intake. Approximately doubling this additional iron intake reduced the risk of inadequacy to 2-12%, but the risk of excess intake reached 22%.

CONCLUSIONS

Providing fortified iron alone may not result in substantial anemia reduction among WRA in India and could have variable benefits and risks across states. Geographically nuanced dietary strategies that include limited fortification and the intake of other beneficial nutrients should be carefully considered.

Changes in Iron Status Are Related to Changes in Brain Activity and Behavior in Rwandan Female University Students: Results from a Randomized Controlled Efficacy Trial Involving Iron-Biofortified Beans

BACKGROUND

Evidence suggests that iron deficiency (ID) affects cognitive performance, as measured in behavior. Although such effects must be mediated by changes in the brain, very few studies have included measures of brain activity to assess this relation.

OBJECTIVE

We tested the hypothesis that provision of iron-biofortified beans would result in improvements in measures of iron status, brain dynamics, and behavior.

METHODS

A double-blind, randomized, intervention study was conducted in 55 women aged 18-27 y with low iron status (serum ferritin <20 µg/L). Women were randomly assigned to consume iron-biofortified (86.1 ppm iron) or comparison beans (50.1 ppm iron) daily for 18 wk. Iron status was assessed by hemoglobin, ferritin, transferrin receptor, and body iron; cognitive performance with 5 computerized tasks; and brain dynamics by concurrent electroencephalography (EEG). All measures were taken at baseline and endline.

RESULTS

The groups did not differ on any measures at baseline. Intention-to-treat analyses revealed significant (all P < 0.05) improvements in hemoglobin (partial effect size attributable to the independent variable, η2 = 0.16), ferritin (η2 = 0.17), and body iron (η2 = 0.10), speed of responding in attentional and mnemonic tasks (η2 = 0.04-0.29), sensitivity and efficiency of memory retrieval (η2 = 0.12-0.55), and measures of EEG amplitude and spectral power (η2 = 0.08 to 0.49). Mediation models provided evidence in support of the hypothesis that changes in iron status produce changes in behavior by way of changes in brain activity.

CONCLUSIONS

Behavioral performance and brain activity, as measured by EEG, are sensitive to iron status, and the consumption of iron-biofortified beans for 18 wk resulted in improvements in measures of both, relative to what was obtained with a comparison bean, in a sample of female university students. Furthermore, the results support the conclusion that changes in brain activity resulting from consumption of biofortified beans mediate the relations between changes in iron biomarkers and changes in cognition. Clinical trial registry: ClinicalTrials.gov Reg No. NCT01594359.

Impact of Double-Fortified Salt with Iron and Iodine on Hemoglobin, Anemia, and Iron Deficiency Anemia: A Systematic Review and Meta-Analysis

Double-fortified salt (DFS) containing iron and iodine has been proposed as a feasible and cost-effective alternative for iron fortification in low- and middle-income countries (LMICs). We conducted a systematic review and meta-analysis from randomized and quasi-randomized controlled trials to 1) assess the effect of DFS on biomarkers of iron status and the risk of anemia and iron deficiency anemia (IDA) and 2) evaluate differential effects of DFS by study type (efficacy or effectiveness), population subgroups, iron formulation (ferrous sulfate, ferrous fumarate, and ferric pyrophosphate), iron concentration, duration of intervention, and study quality. A systematic search with the use of MEDLINE, EMBASE, Cochrane, Web of Science, and other sources identified 221 articles. Twelve efficacy and 2 effectiveness studies met prespecified inclusion criteria. All studies were conducted in LMICs: 10 in India, 2 in Morocco, and 1 each in Côte d'Ivoire and Ghana. In efficacy studies, DFS increased hemoglobin concentrations [standardized mean difference (SMD): 0.28; 95% CI: 0.11, 0.44; P < 0.001] and reduced the risk of anemia (RR: 0.59; 95% CI: 0.46, 0.77; P < 0.001) and IDA (RR 0.37; 95% CI: 0.25, 0.54; P < 0.001). In effectiveness studies, the effect size for hemoglobin was smaller but significant (SMD: 0.03; 95% CI: 0.01, 0.05; P < 0.01). Stratified analyses of efficacy studies by population subgroups indicated positive effects of DFS among women and school-age children. For the latter, DFS increased hemoglobin concentrations (SMD: 0.32; 95% CI: 0.03, 0.60; P < 0.05) and reduced the risk of anemia (SMD: 0.48; 95% CI: 0.34, 0.67; P < 0.001) and IDA (SMD: 0.37; 95% CI: 0.25, 0.54; P < 0.001). Hemoglobin concentrations, anemia prevalence and deworming at baseline, sample size, and study duration were not associated with effect sizes. The results indicate that DFS is efficacious in increasing hemoglobin concentrations and reducing the risk of anemia and IDA in LMIC populations. More effectiveness studies are needed.

Consumption of a Double-Fortified Salt Affects Perceptual, Attentional, and Mnemonic Functioning in Women in a Randomized Controlled Trial in India

Background: Iron deficiency and iron deficiency anemia have been shown to have negative effects on aspects of perception, attention, and memory.Objective: The purpose of this investigation was to assess the extent to which increases in dietary iron consumption are related to improvements in behavioral measures of perceptual, attentional, and mnemonic function.Methods: Women were selected from a randomized, double-blind, controlled food-fortification trial involving ad libitum consumption of either a double-fortified salt (DFS) containing 47 mg potassium iodate/kg and 3.3 mg microencapsulated ferrous fumarate/g (1.1 mg elemental Fe/g) or a control iodized salt. Participants' blood iron status (primary outcomes) and cognitive functioning (secondary outcomes) were assessed at baseline and after 10 mo at endline. The study was performed on a tea plantation in the Darjeeling district of India. Participants (n = 126; 66% iron deficient and 49% anemic at baseline) were otherwise healthy women of reproductive age, 18-55 y.Results: Significant improvements were documented for iron status and for perceptual, attentional, and mnemonic function in the DFS group (percentage of variance accounted for: 16.5%) compared with the control group. In addition, the amount of change in perceptual and cognitive performance was significantly (P < 0.05) related to the amount of change in blood iron markers (mean percentage of variance accounted for: 16.0%) and baseline concentrations of blood iron markers (mean percentage of variance accounted for: 25.0%). Overall, there was evidence that the strongest effects of change in iron status were obtained for perceptual and low-level attentional function.Conclusion: DFS produced measurable and significant improvements in the perceptual, attentional, and mnemonic performance of Indian female tea pickers of reproductive age. This trial was registered at clinicaltrials.gov as NCT01032005.

Double Fortified Salt Intervention Improved Iron Intake But Not Energy and Other Nutrient Intakes in Female Tea Plantation Workers From West Bengal, India

BACKGROUND

Iron deficiency is a global public health concern and has implications on the health status of women in reproductive age.

OBJECTIVE

We hypothesized that improving iron intake with double fortified salt would improve food intake, resulting in higher energy, nutrient intakes, and weight indicators of female tea plantation workers.

METHODS

In this randomized double-masked study, the participants (n = 245) were assigned to receive salt double fortified with iron and iodine (DFS; treatment) or salt fortified with iodine (control) and followed for 7.5 to 9 months. Dietary intakes were measured at three time points, baseline, midpoint, and end line using (1) food frequency questionnaire, (2) 24-hour recall, and (3) weighed lunch intake. Anthropometric measures of height (cm), weight (kg), and mid-upper arm circumference (cm) were also recorded at three time points. Mixed-model repeated-measures approach was used to detect group differences across time.

RESULTS

Double fortified salt improved dietary iron intake in the treatment group compared to the control group ( P < .001). No other dietary or anthropometric differences could be attributed to treatment. Significant effect of time was observed in the intake frequency of major food groups and calcium, vitamin A and C ( P <.001 for all), suggesting an equal effect of seasonality in both the groups.

CONCLUSION

Addition of DFS in the diet improved dietary iron intake but did not affect the intake of energy, other nutrients, or nutritional status indicators. The improvement observed in the dietary iron intake demonstrates that fortification is an effective strategy to address iron deficiency in at-risk populations.

Efficacy of iron-supplement bars to reduce anemia in urban Indian women: a cluster-randomized controlled trial

Background: India's high prevalence of iron-deficiency anemia has largely been attributed to the local diet consisting of nonheme iron, which has lower absorption than that of heme iron.Objective: We assessed the efficacy of the consumption of iron-supplement bars in raising hemoglobin concentrations and hematocrit percentages in anemic (hemoglobin concentration <12 g/dL) Indian women of reproductive age.Design: The Let's be Well Red study was a 90-d, pair-matched, cluster-randomized controlled trial. A total of 361 nonpregnant women (age 18-35 y) were recruited from 10 sites within Mumbai and Navi Mumbai, India. All participants received anemia education and a complete blood count (CBC). Random assignment of anemic participants to intervention and control arms occurred within 5 matched site-pairs. Intervention participants received 1 iron-supplement bar (containing 14 mg Fe)/d for 90 d, whereas control subjects received nothing. CBC tests were given at days 15, 45, and 90. Primary outcomes were 90-d changes from baseline in hemoglobin concentrations and hematocrit percentages. Linear mixed models and generalized estimating equations were used to model continuous and binary outcomes, respectively.Results: Of 179 anemic participants, 136 (76.0%) completed all follow-up assessments (65 intervention and 71 control participants). Baseline characteristics were comparable by arm. Mean hemoglobin and hematocrit increases after 90 d were greater for intervention than for control participants [1.4 g/dL (95% CI: 1.3, 1.6 g/dL) and 2.7% (95% CI: 2.2%, 3.2%), respectively]. The anemia prevalence at 90 d was lower for intervention (29.2%) than for control participants (98.6%) (OR: 0.007; 95% CI: 0.001, 0.04).Conclusions: The daily consumption of an iron-supplement bar leads to increased hemoglobin concentrations and hematocrit percentages and to a lower anemia prevalence in the target population with no reported side effects. This intervention is an attractive option to combat anemia in India. This trial was registered at clinicaltrials.gov as NCT02032615.

Bioavailability of iron, vitamin A, zinc, and folic acid when added to condiments and seasonings

Seasonings and condiments can be candidate vehicles for micronutrient fortification if consumed consistently and if dietary practices ensure bioavailability of the nutrient. In this review, we identify factors that may affect the bioavailability of iron, vitamin A, zinc, and folic acid when added to seasonings and condiments and evaluate their effects on micronutrient status. We take into consideration the chemical and physical properties of different forms of the micronutrients, the influence of the physical and chemical properties of foods and meals to which fortified seasonings and condiments are typically added, and interactions between micronutrients and the physiological and nutritional status of the target population. Bioavailable fortificants of iron have been developed for use in dry or fluid vehicles. For example, sodium iron ethylenediaminetetraacetic acid (NaFeEDTA) and ferrous sulfate with citric acid are options for iron fortification of fish and soy sauce. Furthermore, NaFeEDTA, microencapsulated ferrous fumarate, and micronized elemental iron are potential fortificants in curry powder and salt. Dry forms of retinyl acetate or palmitate are bioavailable fortificants of vitamin A in dry candidate vehicles, but there are no published studies of these fortificants in fluid vehicles. Studies of zinc and folic acid bioavailability in seasonings and condiments are also lacking.