Introduction to the programme guidance for the use of iodised salt in processed foods and its pilot implementation, strengthening strategies to improve iodine status.

Efforts to achieve optimal iodine intake through salt iodisation have focussed primarily on iodisation of household salt. However, there is strong evidence that in most regions of the world, industrially processed foods and condiments are an increasingly important source of dietary salt. In this context The Iodine Global Network (IGN) and partners developed programme guidance to help national programme managers assess the potential contribution of widely consumed industrially processed foods and condiments to iodine intake. The programme guidance additionally aimed to facilitate better understanding of iodised salt use by the processed food industry, review existing salt iodisation legislation for inclusion of food industry salt, and investigate how regulatory monitoring of food industry practices could be strengthened if needed. To evaluate the utility of the guidance in practice and identify areas where it could be improved, the IGN requested expressions of interest to pilot test implementation. Five pilots were implemented in Kenya, North Macedonia, The Republic of Moldova, Sri Lanka and Thailand, with remote technical support from IGN. The pilots demonstrated how evidence from implementation could be used to strengthen existing salt iodisation initiatives. In particular, how modelling existing processed food intake data enhanced understanding of potential or actual iodised salt intake and provided an evidence base for strategic change, as well as encouraging alignment with salt reduction programmes. In summary, the guidance provided a useful framework for national teams to conduct a relatively rapid assessment of the existing programme for achieving optimal iodine nutrition and opportunities to strengthen it. National teams involved with the pilot implementation were highly engaged and motivated by the outcomes. The pilot implementation process resulted in the development of strategic recommendations nationally and provided invaluable feedback to IGN on the utility of the guidance, facilitating development of an improved version.

Modelling the contribution of iodised salt in industrially processed foods to iodine intake in Macedonia.

Evidence from the 1950s showed that Macedonia was iodine deficient. After the introduction of mandatory universal salt iodisation, the country saw a steady increase in iodine intake and decline in goitre prevalence, earning iodine-deficiency free status in 2003. Iodine status assessments in 2007 and 2016 showed adequate iodine intake among school age children (median urinary iodine concentration of 241 µg/L and 236 µg/L respectively). Macedonia participated in piloting the Iodine Global Network Programme Guidance on the use of iodised salt in industrially processed foods to better understand potential iodised salt intake from processed foods. One objective of implementation was to identify the need, opportunities, and required actions to strengthen the processed food component of the national salt iodisation policy. Data from the 2017 Household Consumption and Expenditure Survey (HCES) was used to determine household salt consumption, to identify widely-consumed, salt-containing industrially processed foods, and estimate typical daily intake of these foods. Their estimated contribution to iodine intake was estimated based on their salt content and the percentage of food industry salt that is iodised. Although the study has limitations, including a relatively small selection of foods, the results indicate potential iodine intake from iodised household salt and iodised salt in the selected foods of nearly 300% of the Estimated Average Requirement and over 220% of the Recommended Nutrient Intake for adults. This was approximately 50% of the tolerable safe Upper Level for iodine intake. The study confirmed high daily salt intake (11.2 grams from household salt only). Successful salt reduction would be expected to reduce iodine intake, however, modelling with 10% and 30% reduction implied this is unlikely to put any population group at risk of deficiency. It is recommended that implementation of salt iodisation and salt reduction policies are harmonized, alongside continued regular iodine status monitoring for different population groups.

Estimated contribution of most commonly consumed industrialized processed foods to salt intake and iodine intakes in Sri Lanka.

In Sri Lanka dietary patterns are shifting towards increased consumption of industrially processed foods (IPF). This study aimed to estimate the contribution of IPF to salt and iodine intake and assess the possible impact of salt reduction on iodized salt intake. The assessment was conducted using guidance published by the Iodine Global Network. National nutrition and household income expenditure surveys were used to estimate adult per capita consumption of household salt and commonly consumed salt-containing IPF. Industry and laboratory data were used to quantify salt content of IPF. Modelling estimated the potential and current iodine intake from consumption of household salt and using iodized salt in the identified IPF. Estimates were adjusted to investigate the likely impact on iodine intake of achieving 30% salt reduction. IPF included were bread, dried fish and biscuits, with daily per capita consumption of 32g, 10g and 7g respectively. Daily intake of household salt was estimated to be 8.5g. Potential average national daily iodine intake if all salt in these products was iodized was 166µg. Estimated current daily iodine intake, based on iodization of 78% of household salt and dried fish being made with non-iodized salt, was 111µg nationally, ranging from 90 to 145µg provincially. Estimated potential and current iodine intakes were above the estimated average requirement of 95µg iodine for adults, however, current intake was below the recommended nutrient intake of 150µg. If the 30% salt reduction target is achieved, estimated current iodine intake from household salt, bread and biscuits could decrease to 78µg. The assessment together with data for iodine status suggest that current iodine intake of adults in Sri Lanka is adequate. Recommendations to sustain with reduced salt intake are to strengthen monitoring of population iodine status and of food industry use of iodized salt, and to adjust the salt iodine levels if needed.

Assessment of the contribution of industrially processed foods to salt and iodine intake in Thailand.

Iodization of food grade salt has been mandated in Thailand since 1994. Currently, processed food consumption is increasing, triggered by higher income, urbanization, and lifestyle changes, which affects the source of salt and potentially iodized salt among the population. However, adequate information about the use of iodized salt in processed foods in Thailand is still lacking. Therefore, this study aimed to assess iodine intake through salt-containing processed foods and condiments which were identified using national survey data. Potential iodine intake from iodized salt in food products was modelled using consumption data and product salt content from food labelling and laboratory analysis. Fish sauce, soy sauce and seasoning sauces (salty condiments) have alternative regulation allowing for direct iodization of the final product, therefore modelling was conducted including and excluding these products. Daily salt intake from household salt and food industry salt (including salty condiments) was estimated to be 2.4 g for children 0-5 years of age, 4.6 g for children 6-12 years of age, and 11.5 g for adults. The use of iodized salt in processed foods (excluding salty condiments) met approximately 100% of the estimated average requirement (EAR) for iodine for non-pregnant adults and for children 6 to 12 years of age, and 50% of the EAR for iodine for children aged 0 to 5 years of age. In all cases, iodine intake from processed food consumption was greater than from estimated household iodized salt consumption. Findings suggest that iodized salt from processed foods is an important source of iodine intake, especially in adults. The use of iodized salt by the food industry should be enforced along with population monitoring to ensure sustainability of optimal iodine intake. Currently, the addition of iodine into fish sauce, soy sauce and seasoning sauces has an important role in achieving and sustaining optimal iodine intake.

Household coverage of vitamin A fortification of edible oil in Bangladesh.

Mandatory fortification of edible oil (soybean and palm) with vitamin A was decreed in Bangladesh in 2013. Yet, there is a dearth of data on the availability and consumption of vitamin A fortifiable oil at household level across population sub-groups. To fill this gap, our study used a nationally representative survey in Bangladesh to assess the purchase of fortifiable edible oil among households and project potential vitamin A intake across population sub-groups. Data is presented by strata, age range and poverty-the factors that potentially influence oil coverage. Across 1,512 households, purchase of commercially produced fortifiable edible oil was high (87.5%). Urban households were more likely to purchase fortifiable oil (94.0%) than households in rural low performing (79.7%) and rural other strata (88.1%) (p value: 0.01). Households in poverty were less likely to purchase fortifiable oil (82.1%) than households not in poverty (91.4%) (p <0.001). Projected estimates suggested that vitamin A fortified edible oil would at least partially meet daily vitamin A estimated average requirement (EAR) for the majority of the population. However, certain population sub-groups may still have vitamin A intake below the EAR and alternative strategies may be applied to address the vitamin A needs of these vulnerable sub-groups. This study concludes that a high percentage of Bangladeshi population across different sub-groups have access to fortifiable edible oil and further provides evidence to support mandatory edible oil fortification with vitamin A in Bangladesh.

Regression Analysis to Identify Factors Associated with Urinary Iodine Concentration at the Sub-National Level in India, Ghana, and Senegal.

Single and multiple variable regression analyses were conducted using data from stratified, cluster sample design, iodine surveys in India, Ghana, and Senegal to identify factors associated with urinary iodine concentration (UIC) among women of reproductive age (WRA) at the national and sub-national level. Subjects were survey household respondents, typically WRA. For all three countries, UIC was significantly different (p < 0.05) by household salt iodine category. Other significant differences were by strata and by household vulnerability to poverty in India and Ghana. In multiple variable regression analysis, UIC was significantly associated with strata and household salt iodine category in India and Ghana (p < 0.001). Estimated UIC was 1.6 (95% confidence intervals (CI) 1.3, 2.0) times higher (India) and 1.4 (95% CI 1.2, 1.6) times higher (Ghana) among WRA from households using adequately iodised salt than among WRA from households using non-iodised salt. Other significant associations with UIC were found in India, with having heard of iodine deficiency (1.2 times higher; CI 1.1, 1.3; p < 0.001) and having improved dietary diversity (1.1 times higher, CI 1.0, 1.2; p = 0.015); and in Ghana, with the level of tomato paste consumption the previous week (p = 0.029) (UIC for highest consumption level was 1.2 times lowest level; CI 1.1, 1.4). No significant associations were found in Senegal. Sub-national data on iodine status are required to assess equity of access to optimal iodine intake and to develop strategic responses as needed.

Regression Analysis to Identify Factors Associated with Household Salt Iodine Content at the Sub-National Level in Bangladesh, India, Ghana and Senegal.

Regression analyses of data from stratified, cluster sample, household iodine surveys in Bangladesh, India, Ghana and Senegal were conducted to identify factors associated with household access to adequately iodised salt. For all countries, in single variable analyses, household salt iodine was significantly different (p < 0.05) between strata (geographic areas with representative data, defined by survey design), and significantly higher (p < 0.05) among households: with better living standard scores, where the respondent knew about iodised salt and/or looked for iodised salt at purchase, using salt bought in a sealed package, or using refined grain salt. Other country-level associations were also found. Multiple variable analyses showed a significant association between salt iodine and strata (p < 0.001) in India, Ghana and Senegal and that salt grain type was significantly associated with estimated iodine content in all countries (p < 0.001). Salt iodine relative to the reference (coarse salt) ranged from 1.3 (95% CI 1.2, 1.5) times higher for fine salt in Senegal to 3.6 (95% CI 2.6, 4.9) times higher for washed and 6.5 (95% CI 4.9, 8.8) times higher for refined salt in India. Sub-national data are required to monitor equity of access to adequately iodised salt. Improving household access to refined iodised salt in sealed packaging, would improve iodine intake from household salt in all four countries in this analysis, particularly in areas where there is significant small-scale salt production.

New Statistical Approach to Apportion Dietary Sources of Iodine Intake: Findings from Kenya, Senegal and India.

Progress of national Universal Salt Iodization (USI) strategies is typically assessed by household coverage of adequately iodized salt and median urinary iodine concentration (UIC) in spot urine collections. However, household coverage does not inform on the iodized salt used in preparation of processed foods outside homes, nor does the total UIC reflect the portion of population iodine intake attributable to the USI strategy. This study used data from three population-representative surveys of women of reproductive age (WRA) in Kenya, Senegal and India to develop and illustrate a new approach to apportion the population UIC levels by the principal dietary sources of iodine intake, namely native iodine, iodine in processed food salt and iodine in household salt. The technique requires measurement of urinary sodium concentrations (UNaC) in the same spot urine samples collected for iodine status assessment. Taking into account the different complex survey designs of each survey, generalized linear regression (GLR) analyses were performed in which the UIC data of WRA was set as the outcome variable that depends on their UNaC and household salt iodine (SI) data as explanatory variables. Estimates of the UIC portions that correspond to iodine intake sources were calculated with use of the intercept and regression coefficients for the UNaC and SI variables in each country's regression equation. GLR coefficients for UNaC and SI were significant in all country-specific models. Rural location did not show a significant association in any country when controlled for other explanatory variables. The estimated UIC portion from native dietary iodine intake in each country fell below the minimum threshold for iodine sufficiency. The UIC portion arising from processed food salt in Kenya was substantially higher than in Senegal and India, while the UIC portions from household salt use varied in accordance with the mean level of household SI content in the country surveys. The UIC portions and all-salt-derived iodine intakes found in this study were illustrative of existing differences in national USI legislative frameworks and national salt supply situations between countries. The approach of apportioning the population UIC from spot urine collections may be useful for future monitoring of change in iodine nutrition from reduced salt use in processed foods and in households.

Iodine Intake Estimation from the Consumption of Instant Noodles, Drinking Water and Household Salt in Indonesia.

The objective of this study was to assess the contribution of iodine intake from iodised household salt, iodised salt in instant noodles, and iodine in ground water in five regions of Indonesia. Secondary data analysis was performed using the 2013 Primary Health Research Survey, the 2014 Total Diet Study, and data from food industry research. Iodine intake was estimated among 2719 children, 10-12 years of age (SAC), 13,233 women of reproductive age (WRA), and 578 pregnant women (PW). Combined estimated iodine intake from the three stated sources met 78%, 70%, and 41% of iodine requirements for SAC, WRA and PW, respectively. Household salt iodine contributed about half of the iodine requirements for SAC (49%) and WRA (48%) and a quarter for PW (28%). The following variations were found: for population group, the percentage of estimated dietary iodine requirements met by instant noodle consumption was significantly higher among SAC; for region, estimated iodine intake was significantly higher from ground water for WRA in Java, and from household salt for SAC and WRA in Kalimantan and Java; and for household socio-economic status (SES), iodine intake from household salt was significantly higher in the highest SES households. Enforcement of clear implementing regulations for iodisation of household and food industry salt will promote optimal iodine intake among all population groups with different diets.

Iodine Intake through Processed Food: Case Studies from Egypt, Indonesia, the Philippines, the Russian Federation and Ukraine, 2010-2015.

The current performance indicator for universal salt iodisation (USI) is the percentage of households using adequately iodised salt. However, the proportion of dietary salt from household salt is decreasing with the increase in consumption of processed foods and condiments globally. This paper reports on case studies supported by the Global Alliance for Improved Nutrition (GAIN)-UNICEF USI Partnership Project to investigate processed food industry use of adequately iodised salt in contrasting national contexts. Studies were conducted in Egypt, Indonesia, the Philippines, the Russian Federation, and Ukraine. In all cases, the potential iodine intake from iodised salt in selected food products was modelled according to the formula: quantity of salt per unit of food product × minimum regulated iodine level of salt at production × average daily per capita consumption of the product. The percent of adult recommended nutrient intake for iodine potentially provided by the average daily intake of bread and frequently consumed foods and condiments was from 10% to 80% at the individual product level. The potential contribution to iodine intake from the use of iodised salt in the processed food industry is of growing significance. National USI strategies should encourage co-operative industry engagement and include regulatory monitoring of iodised salt use in the food industry in order to achieve optimal population iodine status.

Household Coverage with Adequately Iodized Salt Varies Greatly between Countries and by Residence Type and Socioeconomic Status within Countries: Results from 10 National Coverage Surveys.

Background: Household coverage with iodized salt was assessed in 10 countries that implemented Universal Salt Iodization (USI).Objective: The objective of this paper was to summarize household coverage data for iodized salt, including the relation between coverage and residence type and socioeconomic status (SES).Methods: A review was conducted of results from cross-sectional multistage household cluster surveys with the use of stratified probability proportional to size design in Bangladesh, Ethiopia, Ghana, India, Indonesia, Niger, the Philippines, Senegal, Tanzania, and Uganda. Salt iodine content was assessed with quantitative methods in all cases. The primary indicator of coverage was percentage of households that used adequately iodized salt, with an additional indicator for salt with some added iodine. Indicators of risk were SES and residence type. We used 95% CIs to determine significant differences in coverage.Results: National household coverage of adequately iodized salt varied from 6.2% in Niger to 97.0% in Uganda. For salt with some added iodine, coverage varied from 52.4% in the Philippines to 99.5% in Uganda. Coverage with adequately iodized salt was significantly higher in urban than in rural households in Bangladesh (68.9% compared with 44.3%, respectively), India (86.4% compared with 69.8%, respectively), Indonesia (59.3% compared with 51.4%, respectively), the Philippines (31.5% compared with 20.2%, respectively), Senegal (53.3% compared with 19.0%, respectively), and Tanzania (89.2% compared with 57.6%, respectively). In 7 of 8 countries with data, household coverage of adequately iodized salt was significantly higher in high- than in low-SES households in Bangladesh (58.8% compared with 39.7%, respectively), Ghana (36.2% compared with 21.5%, respectively), India (80.6% compared with 70.5%, respectively), Indonesia (59.9% compared with 45.6%, respectively), the Philippines (39.4% compared with 17.3%, respectively), Senegal (50.7% compared with 27.6%, respectively) and Tanzania (80.9% compared with 51.3%, respectively).Conclusions: Uganda has achieved USI. In other countries, access to iodized salt is inequitable. Quality control and regulatory enforcement of salt iodization remain challenging. Notable progress toward USI has been made in Ethiopia and India. Assessing progress toward USI only through household salt does not account for potentially iodized salt consumed through processed foods.

Performance of rapid test kits to assess household coverage of iodized salt.

OBJECTIVE: The main indicator adopted to track universal salt iodization has been the coverage of adequately iodized salt in households. Rapid test kits (RTK) have been included in household surveys to test the iodine content in salt. However, laboratory studies of their performance have concluded that RTK are reliable only to distinguish between the presence and absence of iodine in salt, but not to determine whether salt is adequately iodized. The aim of the current paper was to examine the performance of RTK under field conditions and to recommend their most appropriate use in household surveys. DESIGN: Standard performance characteristics of the ability of RTK to detect the iodine content in salt at 0 mg/kg (salt with no iodine), 5 mg/kg (salt with any added iodine) and 15 mg/kg ('adequately' iodized salt) were calculated. Our analysis employed the agreement rate (AR) as a preferred metric of RTK performance. Setting/Subjects Twenty-five data sets from eighteen population surveys which assessed household iodized salt by both the RTK and a quantitative method (i.e. titration or WYD Checker) were obtained from Asian (nineteen data sets), African (five) and European (one) countries. RESULTS: In detecting iodine in salt at 0 mg/kg, the RTK had an AR>90 % in eight of twenty-three surveys, while eight surveys had an AR90 %. CONCLUSIONS: The RTK is not suited for assessment of adequately iodized salt coverage. Quantitative assessment, such as by titration or WYD Checker, is necessary for estimates of adequately iodized salt coverage.