The potential for current sodium and potassium production to support a global switch to the use of potassium-enriched salt: a desktop research study.

OBJECTIVE: Switching regular salt (sodium chloride) to salt enriched with potassium chloride (25 % potassium chloride, 75 % sodium chloride) has been shown to reduce blood pressure and the risk of cardiovascular diseases. We sought to define the potential for the current production of sodium chloride and potassium chloride to support a global switch to the use of potassium-enriched salt. DESIGN: We summarised data from geological surveys, government reports and trade organisations describing the global production and supply of sodium chloride and potash (the primary source of potassium chloride) and compared this to potential requirements for potassium-enriched salt. SETTING: Global. PARTICIPANTS: Not applicable. RESULTS: Approximately 280 million tonnes of sodium chloride were produced in 2020 with China and the USA the main producers. Global production of potash from which potassium chloride is extracted was about forty-four million tonnes with Canada, Belarus, Russia and China providing 77 % of the world's supply. There were forty-eight countries in which potassium-enriched salt is currently marketed with seventy-nine different brands identified. Allowing for loss of salt between manufacture and consumption, a full global switch from regular salt to potassium-enriched salt would require about 9·7 million tonnes of sodium chloride to be replaced with 9·7 million tonnes of potassium chloride annually. CONCLUSIONS: Significant upscaling of the production of potassium chloride and the capacity of companies able to manufacture potassium-enriched salt, as well as a robust business case for the switch to potassium chloride, would be required.

Switching the World's Salt Supply-Learning from Iodization to Achieve Potassium Enrichment.

Sodium is an essential dietary component, but excess sodium intake can lead to high blood pressure and an increased risk of cardiovascular disease. Many national and international bodies, including the World Health Organization, have advocated for population-wide sodium reduction interventions. Most have been unsuccessful due to inadequate sodium reduction by food industry and difficulties in persuading consumers to add less salt to food. Recent research highlights potassium-enriched salt as a new, feasible, acceptable, and scalable approach to reducing the harms caused by excess sodium and inadequate potassium consumption. Modeling shows that a global switch from regular salt to potassium-enriched salt has the potential to avert millions of strokes, heart attacks, and premature deaths worldwide each year. There will be many challenges in switching the world's salt supply to potassium-enriched salt, but the success of universal salt iodization shows that making a global change to the manufacture and use of salt is a tractable proposition. This in-depth review of universal salt iodization identified the importance of a multisectoral effort with strong global leadership, the support of multilateral organizations, engagement with the salt industry, empowered incountry teams, strong participation of national governments, understanding the salt supply chain, and a strategic advocacy and communication plan. Key challenges to the implementation of the iodization program were costs to government, industry, and consumers, industry concerns about consumer acceptability, variance in the size and capabilities of salt producers, inconsistent quality control, ineffective regulation, and trade-related regulatory issues. Many of the opportunities and challenges to universal salt iodization will likely also be applicable to switching the global salt supply to iodized and potassium-enriched salt.

Global Coverage of Mandatory Large-Scale Food Fortification Programs: A Systematic Review and Meta-Analysis.

Food fortification with micronutrients is widely implemented to reduce micronutrient deficiencies and related outcomes. Although many factors affect the success of fortification programs, high population coverage is needed to have a public health impact. We aimed to provide recent global coverage estimates of salt, wheat flour, vegetable oil, maize flour, rice, and sugar among countries with mandatory fortification legislation. The indicators were the proportion of households consuming the: food, fortifiable food (that is, industrially processed), fortified food (to any extent), and adequately fortified food (according to national or international standards). We estimated the number of individuals reached with fortified foods. We systematically retrieved and reviewed all applicable evidence from: published reports and articles from January 2010 to August 2021, survey lists/databases from key organizations, and reports/literature received from key informants. We analyzed data with R statistical package using random-effects meta-analysis models. An estimated 94.4% of households consumed salt, 78.4% consumed fortified salt (4.2 billion people), and 48.6% consumed adequately fortified salt in 64, 84, and 31 countries, respectively. Additionally, 77.4% of households consumed wheat flour, 61.6% consumed fortifiable wheat flour, and 47.1% consumed fortified wheat flour (66.2 million people) in 15, 8, and 10 countries, respectively, and 87.0% consumed vegetable oil, 86.7% consumed fortifiable oil, and 40.1% consumed fortified oil (123.9 million people) in 10, 7, and 5 countries, respectively. Data on adequately fortified wheat flour and vegetable oil and coverage indicators for maize flour, rice, and sugar were limited. There are major data gaps on fortification coverage for most foods except salt. All countries with mandatory fortification programs should generate and use more coverage data to assess program performance and adjust programs as needed to realize their potential to reduce micronutrient deficiencies (PROSPERO CRD42021269364).

A review of portable quantitative and semi-quantitative devices for measurement of vitamin A in biological samples.

Background: We catalog and summarize evidence of the analytical performance of portable quantitative and semi-quantitative devices for the assessment of vitamin A status and vitamin A deficiency (VAD) in various biological samples-including whole blood, plasma, serum, and milk-in addition to VAD determination by functional indicators such as pupillary response. Methods: We searched the literature for published research articles, patents, and information from manufacturers of mobile devices, particularly those appropriate for low-resource settings. The included devices were required to be portable (lightweight and ideally not needing a power outlet) and to measure vitamin A as well as define VAD. Eligible studies compared a portable device to a reference standard of high-performance liquid chromatography for blood and milk, or a Goldmann-Weekers dark adaptometer for eyes/vision. Where available, identified devices were compared with reference methods across several performance criteria. When possible, we compared the device's performance reported in published studies against the stated performance criteria from the manufacturers' websites. Results: We catalogued 25 portable devices for measuring vitamin A and/or VAD via biological samples. We also identified 18 comparison studies (plus associated reports) assessing nine methods: the iCheck Fluoro, iCheck Carotene, CRAFTi, Tidbit with or without the HYPER filtration system, custom field-friendly immunoassays, and microfluidic assays for blood; the iCheck Fluoro and iCheck Carotene for milk; and the Scotopic Sensitivity Tester-1 for eye function. Conclusions: The iCheck Fluoro and iCheck Carotene are commercially available for use and are acceptable for measuring vitamin A in blood and milk samples, according to the available validation data. Many of the other identified devices, including other portable fluorometers, photometers, immunoassays, microfluidics-based devices, and dark adaptometers, were proofs of concept and not yet commercially available. Furthermore, none of these other devices included manufacturer-described device performance criteria to compare with descriptions from experimental studies. Several gaps remain, including studies comparing the other portable devices against a reference standard, particularly for functional indicators of vitamin A status/deficiency; available manufacturer-reported device performance criteria against which to compare future results of investigations; and more comprehensive reporting of validation metrics including sensitivity, specificity, precision, and Bland-Altman analysis.

Portable Devices for Measurement of Vitamin A Concentrations in Edible Oil: Field Readiness of Available Options.

Vitamin A (VA) deficiency continues to be a major global health issue, despite measures to increase VA intake via consumption of staple foods such as edible oil. Portable quantitative and semiquantitative devices or test kits for internal quality control have the potential to overcome some of the limitations of traditional methods of testing, such as centralized laboratory, expensive equipment, and specially trained staff. This landscape analysis and comprehensive systematic mini-review catalogs and summarizes evidence on the analytical performance of portable quantitative and semiquantitative devices and test kits for the analysis of VA in edible oil. Studies or reports detailing the usability and validation of portable devices and/or test kits, as well as studies comparing device/test kit performance to a reference standard such as high-performance liquid chromatography (HPLC), were included. Identified devices and test kits were compared for performance versus the reference standard, usability, availability, and other characteristics. We identified four portable methods: two devices, the iCheck CHROMA and iCheck Chroma 3 from BioAnalyt; and two test kits, the QuickView from Bagco Enterprises and the Strategic Alliance for the Fortification of Vegetable Oils (SAFO) Test Kit by Badische Anilin and Soda Fabrik (BASF). Included studies reported the following: an internal validation of the portable method, a comparison of the portable method against a reference standard, a comparison of the portable method against another portable method, and several videos and company websites, which detailed device characteristics. iCheck CHROMA and QuickView quantified VA concentrations with high accuracy and precision compared to the reference standard for field-based quantification, were user-friendly, and provided results within 5 min. iCheck Chroma 3 requires more robust validation against a reference standard. We did not find data on internal validation or comparison against a reference standard for the current version of the SAFO test. Compared to QuickView and SAFO, the iCheck devices can transfer results to a hard drive or the Web, have an online order form for purchase, and meet a minimal set of criteria for point-of-need devices. iCheck, QuickView, and SAFO can quantify VA concentrations in the edible oils tested and determine whether a fortified oil meets country standards. Additional research is needed to validate these devices and test kits across additional oil types and document the ability to meet the minimal criteria for point-of-need devices suggested in this mini-review. Validation against a reference standard is required for SAFO. The limited number of portable methods available may be due to market saturation. Future market and use case analyses to inform the market size and utility of the different tests with publicly available data will allow new manufacturers, particularly those in lower-to-middle-income countries, to enter the market.

The Unfinished Agenda for Food Fortification in Low- and Middle-Income Countries: Quantifying Progress, Gaps and Potential Opportunities.

Large-scale food fortification (LSFF) is a cost-effective intervention that is widely implemented, but there is scope to further increase its potential. To identify gaps and opportunities, we first accessed the Global Fortification Data Exchange (GFDx) to identify countries that could benefit from new fortification programs. Second, we aggregated Fortification Assessment Coverage Toolkit (FACT) survey data from 16 countries to ascertain LSFF coverage and gaps therein. Third, we extended our narrative review to assess current innovations. We identified 84 countries as good candidates for new LSFF programs. FACT data revealed that the potential of oil/ghee and salt fortification is not being met due mainly to low coverage of adequately fortified foods (quality). Wheat, rice and maize flour fortification have similar quality issues combined with lower coverage of the fortifiable food at population-level (< 50%). A four-pronged strategy is needed to meet the unfinished agenda: first, establish new LSFF programs where warranted; second, systems innovations informed by implementation research to address coverage and quality gaps; third, advocacy to form new partnerships and resources, particularly with the private sector; and finally, exploration of new fortificants and vehicles (e.g. bouillon cubes; salt fortified with multiple nutrients) and other innovations that can address existing challenges.