Quadruple fortification of salt for the delivery of iron, iodine, folic acid, and vitamin B12 to vulnerable populations

Biological properties of vitamin B12

Vitamin B12, cobalamin, is indispensable for humans owing to its participation in two biochemical reactions: the conversion of l-methylmalonyl coenzyme A to succinyl coenzyme A, and the formation of methionine by methylation of homocysteine. Eukaryotes, encompassing plants, fungi, animals and humans, do not synthesise vitamin B12, in contrast to prokaryotes. Humans must consume it in their diet. The most important sources include meat, milk and dairy products, fish, shellfish and eggs. Due to this, vegetarians are at risk to develop a vitamin B12 deficiency and it is recommended that they consume fortified food. Vitamin B12 behaves differently to most vitamins of the B complex in several aspects, e.g. it is more stable, has a very specific mechanism of absorption and is stored in large amounts in the organism. This review summarises all its biological aspects (including its structure and natural sources as well as its stability in food, pharmacokinetics and physiological function) as well as causes, symptoms, diagnosis (with a summary of analytical methods for its measurement), prevention and treatment of its deficiency, and its pharmacological use and potential toxicity.

Modeling the Contribution of Multiple Micronutrient Fortification of Salt to Daily Nutrient Intake Among the Ethiopian Population

Background

Salt is an affordable commodity and has wide coverage regardless of economic and social status and, hence, could be suitable vehicle for multiple micronutrient fortification.

Objectives

This study aimed to simulate the contribution folic acid and zinc fortification of iodized salt to nutrient intake among the Ethiopian population.

Methods

The 2013 Ethiopian National Food Consumption Survey and various food composition tables were used to estimate baseline individual-level micronutrient intake. Usual intake was estimated using the Simulating Intake of Micronutrients for Policy Learning and Engagement macro tool. Discretionary salt consumption was calculated from total salt intake estimated using urinary sodium excretion. Fortificant addition rates were set to obtain maximum nutrient intake while simultaneously constraining that population with intake above the tolerable upper intake level to <5%. Addis Ababa and Somali (N = 2271), the regions with relatively the lowest and highest micronutrient deficiency prevalence in Ethiopia, were selected.

Result

Baseline median intake of Zn was below the estimated average requirement for all demographic groups. Inadequate Zn intake ranged from 73% to 99%, the highest prevalence being observed among women in lower class of wealth quintiles from Somali region. Dietary folate inadequacy was as low as 2% among men in Addis Ababa but almost all (99%) women from Somali region had inadequate folate intake. Calculated discretionary salt intake was 7.5 g/d for adult men and women and 3.4 g/d for children. With addition 0.8 mg Zn and 30 μg of folic acid per gram of salt, multiple salt fortification is estimated to reduce Zn inadequacy by 38 percentage points in urban areas and19 percentage points in rural areas. Modeled reduction in folate inadequacy were 18% in urban areas and 22% in rural areas.

Conclusions

Multiple salt fortification could be an effective approach to address micronutrient adequacy in Ethiopia given efficacious, technological, and economical feasibility.

Cyclodextrins and their potential applications for delivering vitamins, iron, and iodine for improving micronutrient status

Cyclodextrins (CDs) have been investigated as potential biopolymeric carriers that can form inclusion complexes with numerous bioactive ingredients. The inclusion of micronutrients (e.g. vitamins or minerals) into cyclodextrins can enhance their solubility and provide oxidative or thermal stability. It also enables the formulation of products with extended shelf-life. The designed delivery systems with CDs and their inclusion complexes including electrospun nanofibers, emulsions, liposomes, and hydrogels, show potential in enhancing the solubility and oxidative stability of micronutrients while enabling their controlled and sustained release in applications including food packaging, fortified foods and dietary supplements. Nano or micrometer-sized delivery systems capable of controlling burst release and permeation, or moderating skin hydration have been reported, which can facilitate the formulation of several personal and skin care products for topical or transdermal delivery of micronutrients. This review highlights recent developments in the application of CDs for the delivery of micronutrients, i.e. vitamins, iron, and iodine, which play key roles in the human body, emphasizing their existing and potential applications in the food, pharmaceuticals, and cosmeceuticals industries.

Recent Advances in Dietary Sources, Health Benefits, Emerging Encapsulation Methods, Food Fortification, and New Sensor-Based Monitoring of Vitamin B12: A Critical Review

In this overview, the latest achievements in dietary origins, absorption mechanism, bioavailability assay, health advantages, cutting-edge encapsulation techniques, fortification approaches, and innovative highly sensitive sensor-based detection methods of vitamin B12 (VB12) were addressed. The cobalt-centered vitamin B is mainly found in animal products, posing challenges for strict vegetarians and vegans. Its bioavailability is highly influenced by intrinsic factor, absorption in the ileum, and liver reabsorption. VB12 mainly contributes to blood cell synthesis, cognitive function, and cardiovascular health, and potentially reduces anemia and optic neuropathy. Microencapsulation techniques improve the stability and controlled release of VB12. Co-microencapsulation of VB12 with other vitamins and bioactive compounds enhances bioavailability and controlled release, providing versatile initiatives for improving bio-functionality. Nanotechnology, including nanovesicles, nanoemulsions, and nanoparticles can enhance the delivery, stability, and bioavailability of VB12 in diverse applications, ranging from antimicrobial agents to skincare and oral insulin delivery. Staple food fortification with encapsulated and free VB12 emerges as a prominent strategy to combat deficiency and promote nutritional value. Biosensing technologies, such as electrochemical and optical biosensors, offer rapid, portable, and sensitive VB12 assessment. Carbon dot-based fluorescent nanosensors, nanocluster-based fluorescent probes, and electrochemical sensors show promise for precise detection, especially in pharmaceutical and biomedical applications.

Women in Selected Communities of Punjab, India Have a High Prevalence of Iron, Zinc, Vitamin B12, and Folate Deficiencies: Implications for a Multiply-Fortified Salt Intervention

Dietary intake and biomarkers of micronutrient status of 100 non-pregnant women of reproductive age (NPWRA) were assessed to determine optimal levels of iron, zinc, vitamin B12, and folic acid to include in multiply-fortified salt (MFS) that will be evaluated in an upcoming trial. Weighed food records were obtained from participants to measure intake of micronutrients and discretionary salt, and to assess adequacy using Indian Nutrient Reference Values (NRVs). Statistical modeling was used to determine optimal fortification levels to reduce inadequate micronutrient intake while limiting intake above the upper limit. Fasting blood samples were obtained to assess iron, zinc, vitamin B12, and folate status. In usual diets, inadequate intake of iron (46%), zinc (95%), vitamin B12 (83%), and folate (36%) was high. Mean intake of discretionary salt was 4.7 g/day. Prevalence estimates of anemia (37%), iron deficiency (67%), zinc deficiency (34%), vitamin B12 insufficiency (37%), and folate insufficiency (70%) were also high. Simulating the addition of optimized MFS to usual diets resulted in percentage point (pp) reductions in inadequate intake by 29 pp for iron, 76 pp for zinc, 81 pp for vitamin B12, and 36 pp for folate. MFS holds potential to reduce the burden of micronutrient deficiencies in this setting.

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.

NaCl Crystals as Carriers for Micronutrient Delivery

Iron deficiency leading to anemia is one of the most severe and important nutritional deficiencies in the world today. To combat this deficiency, the fortification of food products with iron is a natural way to increase the global iron uptake. Here, we report a novel strategy for iron encapsulation in NaCl crystals via microscopic inclusions containing dissolved iron salt. The liquid inclusions embedded in the crystal insulate the reactive iron salts from their environment while assuring that iron is in a soluble and bioavailable form. While the size distribution of inclusions remains independent of the evaporation conditions, their density increases during crystallization at lower relative humidity. Using Raman confocal microspectroscopy, we have been able to analyze the morphology, length/thickness ratio, of inclusions and show that inclusions evolve toward a plate-like structure with the increase in size. By growing a pure NaCl shell around the iron-containing NaCl crystals, the stability of the composite crystals can be even further enhanced. The role of halite crystals as a carrier for iron fortification opens the way for the delivery of other types of micronutrients by including them in table salt.

Nanofortification of vitamin B-complex in food matrix: Need, regulations, and prospects

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Overview of nanomaterials to fortify food with vitamin B-complex.

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Nanofortification of food with vitamin B-complex to overcome conventional fortification challenges.

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Regulatory aspects, prospects, and upcoming trends of this indispensable technology are also discussed.

Micronutrient malnutrition (or hidden hunger) caused by vitamin B-complex deficiency is a significant concern in the growing population. Vitamin B-complex plays an essential role in many body functions. With the introduction of nanotechnology in the food industry, new and innovative techniques have started to develop, which holds a promising future to end malnutrition and help achieve United Nations Sustainable Developmental Goal-2 (UN SDG-2), named as zero hunger. This review highlights the need for nanofortification of vitamin B-complex in food matrix to address challenges faced by conventional fortification methods (bioavailability, controlled release, physicochemical stability, and shelf life). Further, different nanomaterials like organic, inorganic, carbon, and composites along with their applications, are discussed in detail. Among various nanomaterials, organic nanomaterials (lipid, polysaccharides, proteins, and biopolymers) were found best for fortifying vitamin B-complex in foods. Additionally, different regulatory aspects across the globe and prospects of this upcoming field are also highlighted in this review.

Optimization of the color masking and coating unit operations for microencapsulating ferrous fumarate for double fortification of salt

A new coating formulation was developed to eliminate the factor that caused black spots on the iron premix surface, used for making Double Fortified Salt. The formulation is a suspension of titanium dioxide in soy stearin, prepared with ethanol and dichloromethane and applied with a glass sprayer and pan coater. 0–20% ^w/_w titanium dioxide was suspended in 10% ^w/_w soy stearin/hydroxypropyl methylcellulose. Coating with a suspension of 15% ^w/_w TiO₂ in 10% ^w/_w soy stearin ensured that all the TiO₂ adheres to the premix surface, giving no chance for the recycling of iron contaminated TiO₂, which caused the black spot. The new coating formulation ensured that over 90% iodine in Double Fortified Salt was retained after 6 months at 45 °C, 60–70% RH. The whiteness of the premix (L* = 86.4) matched the Double Fortified Salt whiteness (L* = 86.8). Thus, making the new coating method as effective as the previous in desirable characteristics. More so, the new coating method simplifies the existing method by merging the previous color masking, and double coating steps into one step.

Role of Vitamin B12 and Folate in Metabolic Syndrome

Metabolic syndrome (MS) is a collection of pathological metabolic conditions that includes insulin resistance, central or abdominal obesity, dyslipidemia, and hypertension. It affects large populations worldwide, and its prevalence is rising exponentially. There is no specific mechanism that leads to the development of MS. Proposed hypotheses range from visceral adiposity being a key factor to an increase in very-low-density lipoprotein and fatty acid synthesis as the primary cause of MS. Numerous pharmaceutical therapies are widely available in the market for the treatment of the individual components of MS. The relationship between MS and vitamin B complex supplementation, specifically folic acid and vitamin B12, has been a subject of investigation worldwide, with several trials reporting a positive impact with vitamin supplementation on MS.

In this study, an all-language literature search was conducted on Medline, Cochrane, Embase, and Google Scholar till September 2021. The following search strings and Medical Subject Headings (MeSH) terms were used: “Vitamin B12,” “Folate,” “Metabolic Syndrome,” and “Insulin Resistance.” We explored the literature on MS for its epidemiology, pathophysiology, newer treatment options, with a special focus on the effectiveness of supplementation with vitamins B9 and B12.

According to the literature, vitamin B12 and folate supplementation, along with a host of novel therapies, has a considerable positive impact on MS. These findings must be kept in mind while designing newer treatment protocols in the future.

Optimization of Unit Operations for Microencapsulating Ferrous Fumarate During Scale-Up of Double Fortification of Salt with Iron and Iodine

Objectives

This study evaluates factors responsible for the floating of iron premix in double fortified salt (DFS), which initially affected the large-scale implementation of the salt fortification program in India, and provides solutions to the scale-up of the technology.

Materials and Methods

To mitigate this time-sensitive scale-up challenge. First, the iron premix samples were obtained from the industrial scale-up pilot studies in India, evaluated for the impact of the amount of coating material (5 per cent, 7.5 per cent, and 10 per cent (in weight)), type of formulation (soy stearin, SEPIFILM and hydroxypropyl methylcellulose), amount of titanium dioxide (25-35 per cent (in weight)) used for color masking; Second, we studied the effect of change in the composition of the coating, from 10 per cent (in weight) soy stearin to a double coat with 5 per cent (in weight) hydroxypropyl methylcellulose and 5 per cent soy stearin or 10 per cent soy stearin and 1 per cent (in weight) lecithin mixture, on particle density, floating or sinking property of the iron premix, and on the stability of iodine in the DFS.

Results

It was observed that the hydrophobic nature and the amount of soy stearin used for coating caused the floating issue. The double coating with 5 per cent hydroxypropyl methylcellulose and 5 per cent soy stearin was preferred because lecithin in soy stearin enhanced the moisture-aided adverse interaction between iron and iodine. Shelf-life storage studies proved over 80 per cent iodine retention after 12 months of storage in the DFS formulated with iron premix double-coated with hydroxypropyl methylcellulose and soy stearin.

Conclusion

This proffered solution enabled the full implementation of the double fortification program in India.

Folic acid fortification of double fortified salt

The addition of folic acid to Double Fortified Salt (with iron and iodine) aims to simultaneously ameliorate three major micronutrient deficiencies in vulnerable populations. To make Triple Fortified Salt, we added folic acid to the iodine solution (first method) and the iron premix (second method) that are used to fortify salt with iron and iodine. When added through the solution, sodium carbonate was needed to dissolve folic acid and to adjust pH. Alternately, folic acid was added either to the iron core or sandwiched between the core and TiO₂ layer of the iron premix. Folic acid and iodine were stable in all cases, retaining more than 70% of the added micronutrients after six months at 45 °C/60-70% relative hu. Adding folic acid to the premix's iron core is preferred as folic acid retention was slightly higher, and the added folic acid did not impact the salt's colour. The additional cost for adding the micronutrients to salt is about 27¢/person per year. Folic acid in the fortified salt made with the preferred method was stable in cooking and did not affect selected cooked foods' sensory properties. The technology is a cost-effective approach for simultaneously combating iron, iodine, and folic acid deficiencies.