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IZiNCG Awarded New Grant from the Bill & Melinda Gates Foundation to Evaluate the Nutritional Impact of Multiply-Fortified Salt Among Women of Reproductive Age in India 

IZiNCG Awarded New Grant from the Bill & Melinda Gates Foundation to Evaluate the Nutritional Impact of Multiply-Fortified Salt Among Women of Reproductive Age in India 

IZiNCG is pleased to announce the receipt of a grant from the Bill & Melinda Gates Foundation to evaluate the nutritional impact of quintuply-fortified salt vs. standard iodised salt for the improvement of micronutrient status among non-pregnant women of reproductive age in Haryana, India. This project is a collaborative effort primarily between IZiNCG, the Postgraduate Institute of Medical Education and Research (PGIMER), and the Haryana State Government.

Why women of reproductive age?

Women of reproductive age (WRA) and young children are particularly vulnerable to multiple micronutrient deficiencies, and prevalences of deficiency remain unacceptably high in India. The 2015-2016 National Family Health Survey revealed that over half of non-pregnant WRA in India are anaemic. A recent survey of 866 WRA in Haryana demonstrated the co-occurrence of multiple micronutrient deficiencies: 75% of WRA had iron deficiency, 80% had folate insufficiency, and 82% had vitamin B12 deficiency (unpublished observations).  Although plasma zinc concentrations were not assessed, the high prevalence of stunting and the low level of absorbable zinc in the national food supply are suggestive of a high prevalence of zinc deficiency.

 

Why zinc, iron, vitamin B12 and folate?

Zinc, iron, vitamin B12, and folate are critically important for several biological processes related to a healthy pregnancy and the optimal growth and development of the foetus and offspring. Thus, deficiencies in these micronutrients are associated with several adverse health outcomes ranging from preterm and small-for-gestational-age births, neural tube defects, stunting and childhood diarrhoea.  These health problems are widespread in India where more than 3.5 million infants are born preterm each year, nearly 10% of children under 5 have had diarrhoea in the previous 2 weeks, and 38% of children under 5 are stunted. A recent analysis estimated that the prevalence of neural tube defects in South Asia is 32 per 10,000 live births. Clearly, there is an urgent need to improve the micronutrient status of Indian WRA and their children.

Photo credit: World Bank Photo Collection

Photo credit: World Bank Photo Collection

Salt as a novel vehicle for multiple micronutrient fortification

Micronutrient fortification of a staple food or condiment can be an effective strategy for improving the micronutrient status of a population, as the approach is cost-effective, utilises existing delivery systems, can deliver multiple micronutrients simultaneously, and does not require behaviour change by the population.

Salt is an attractive vehicle for multiple micronutrient fortification in India, as it is universally consumed in fairly consistent amounts. India already has excellent coverage of iodized salt and has recently scaled up the distribution of salt fortified with iodine and iron (double-fortified salt).

Extensive research conducted in various settings has shown that double-fortified salt significantly improves iron status in nutritionally vulnerable groups. With new technology developed by the University of Toronto, it is now possible to fortify salt with multiple micronutrients, including zinc, vitamin B12, and folic acid, in addition to iron and iodine.

While salt fortified with encapsulated ferrous fumarate is already being produced at scale and extensively consumed by large populations in India, the planned study proposes to conduct a head-to-head comparison with ferric pyrophosphate likely in combination with citric acid and trisodium citrate (to enhance iron absorption) in an encapsulated medium that is under development and test whether sensory qualities could be improved further.

Plan for the study 

The study will be conducted in two phases. Phase 1 will include formative research involving a dietary assessment to ascertain habitual salt intake and dietary intake of micronutrients; qualitative research to understand salt procurement, storage, and utilization practices; as well as sensory and acceptability testing of the quintuply-fortified salts.

Phase 2 will be a double-blind, randomised controlled efficacy trial where 750 women of reproductive age will be randomised to 1 of 3 groups: 1) quintuply fortified salt with iron in the form of encapsulated ferrous fumarate; 2) quintuply fortified salt with iron in the form of ferric pyrophosphate; and 3) iodised salt. In brief, participating women will be provided with the assigned study salt on a monthly basis for 12 months and blood samples will be taken at baseline, 6 months, and 12 months. The primary outcome will be micronutrient status as measured by the change in biomarkers of zinc, iron, folate, vitamin B12 and iodine status. Secondary outcomes to be assessed include DNA damage, essential fatty metabolism and cognition. 

If proven efficacious, MFS has the potential not only to improve the micronutrient status of WRA, but also lead to improved perinatal outcomes, and better micronutrient status in their offspring. Together with our collaborators, IZiNCG is excited to initiate this study!

 

Collaborators: PGIMER, Haryana State Government, SWACH Foundation, WHO Southeast Asia, the University of Toronto, Tata Trusts/ The India Nutrition Initiative, ETH Zürich, JVS Foods, St. John’s Research Institute, University of Colorado Denver, University of California Davis, Eurofins, University of Otago, University of Nottingham, VitMin laboratory.

 

Read more:

Strategies for promoting zinc nutrition

Zinc supplementation during pregnancy

Zinc Fortification Task Force 

Plasma/serum zinc in national surveys - barriers and enablers

Plasma/serum zinc in national surveys - barriers and enablers

“Micronutrient deficiencies are estimated to impact a significant number of people around the world, but there remains far too little information on micronutrient status and deficiencies. More essential information and surveillance need to be gathered to make substantial progress on global targets.” 

Global Nutrition Report 2018

There is an urgent need for more and better data on the zinc status of vulnerable populations to effectively target and monitor zinc intervention programs. Plasma/serum zinc concentration is endorsed as the best available biomarker of zinc status, particularly for assessing the risk of zinc deficiency in target population groups such as preschool-aged children and women of reproductive age. But to date, national level plasma/serum zinc data for any population group exist for only 26 countries:

Percentage of pre-school children with low plasma or serum zinc concentrations ( map generated using data from WHO Micronutrient Database )

Percentage of pre-school children with low plasma or serum zinc concentrations (map generated using data from WHO Micronutrient Database)

In an effort to increase the availability and utilisation of high-quality data on zinc status at the national level in low- and middle-income countries, IZiNCG will carry out key informant interviews with survey representatives from countries where a national nutrition survey has recently been carried out. We want to better understand the hurdles and enabling factors to the inclusion of plasma/serum zinc in national surveys, and plan to talk with both those who included the assessment of plasma/serum zinc, and those who omitted it.  

Plasma/serum zinc is not the easiest of biomarkers to collect. By identifying factors that have enabled plasma/serum zinc assessment along with challenges that remain, we hope to facilitate the sharing of knowledge between countries and to promote the inclusion of plasma/serum zinc in future surveys. Findings from this project are expected early-2020.

Zinc Fortification Task Force initiates efforts to enhance the impact of zinc fortification interventions

Zinc Fortification Task Force initiates efforts to enhance the impact of zinc fortification interventions

Why a Zinc Fortification Task Force?

Fortification of staple foods and/or condiments with zinc appears to be a promising strategy for improving zinc status at the population level in low- and middle-income countries because of its relatively low cost and long-term sustainability. The motivation for establishing a Zinc Fortification Task Force is to progress IZiNCG’s position and recommendations related to zinc fortification, taking into account recent evidence, existing global guidelines, and the fact that mandatory zinc fortification is in place in more than 30 countries. The Task Force harnesses the perspectives of the Food Fortification Initiative, the Global Alliance for Improved Nutrition and Helen Keller International together with IZiNCG.

 

IZiNCG’s current stance on zinc fortification 

A review in IZiNCG’s 2009 Technical Document no. 2 summarised evidence showing that fortifying staple foods with zinc increases total daily zinc absorption, does not adversely affect the absorption of other minerals, is not associated with adverse effects and is a relatively low-cost intervention (1). Therefore, IZiNCG’s recommendation following this review was that countries should consider including zinc in mass and targeted fortification programs in populations at high risk of zinc deficiency. However, the review also pointed to the paucity of evidence on the efficacy and effectiveness of fortification programs, and that only a few studies had found a positive impact on plasma/serum zinc or functional indicators of zinc status.

Recent reviews

A 2016 Cochrane review of zinc fortification concluded the same: given the relatively small number of trials and participants, further investigation of the effects of zinc fortification was needed (2). However, the Cochrane review excluded many studies on the basis that zinc was not the only nutrient which differed between intervention and control groups, despite plasma/serum zinc being measured as an outcome. While such comparisons may be useful from an epidemiological perspective, they may not fully capture the real-world context.  For example, 34 countries have mandatory zinc fortification in place, with zinc being part of a premix with several other micronutrients. In a very recent review of large-scale food fortification on vitamin A, iodine, iron and folic acid status and health outcomes, this “real-world impact” was at the centre (3). However, this latter review excluded trials with less than 1000 participants, which would be too limiting in the case of available publications on zinc fortification.

School meal_WB photo.jpg

Planned work of the taskforce 

The overarching goal of the task force is to assess the efficacy and effectiveness of zinc fortification interventions, and to identify opportunities to enhance impact. The first activity is to produce an update to the previous zinc fortification systematic reviews, summarising the additional evidence now available on zinc fortification. In addition to determining the impact of zinc fortification on zinc-related biochemical and functional outcomes, the review will attempt to answer the following other questions: 

  • What is the adequate dosage and duration of exposure required to show an effect?

  • What proportion reduction in zinc deficiency can we expect to see as a result of zinc fortification, and which groups may require additional/complementary interventions? 

  • Which indicators should be recommended for evaluating zinc fortification programs?

  • What do we know about novel/alternative vehicles for zinc fortification? 

In parallel, the Zinc Fortification Task Force also wants to capture the lessons learnt and identify knowledge and resource gaps in countries with existing national zinc fortification programs. Which evidence did they act on? Which barriers are they facing? Likewise, the Task Force plans to explore the perspectives of countries with a high burden of zinc deficiency without zinc fortification in place, and the feasibility of zinc fortification as a successful strategy in such settings. 

We hope that the results from the activities in this first phase of the Zinc Fortification Task Force will be available by July 2020, and that this effort will help inform renewed global commitments to food fortification. 

 

References

  1. Hess SY, Brown KH. Impact of zinc fortification on zinc nutrition. Food Nutr Bull. 2009 Mar;30(1 Suppl):S79-107. 

  2. Shah D, Sachdev HS, Gera T, De-Regil LM, Peña-Rosas JP. Fortification of staple foods with zinc for improving zinc status and other health outcomes in the general population. Cochrane Database Syst Rev. 2016 Jun 9;(6):CD010697.

  3. Keats EC, Neufeld LM, Garrett GS, Mbuya MNN, Bhutta ZA. Improved micronutrient status and health outcomes in low- and middle-income countries following large-scale fortification: evidence from a systematic review and meta-analysis. Am J Clin Nutr. 2019 Jun 1;109(6):1696-1708.

Read more about strategies for promoting zinc nutrition here.

Recent publication: A dynamic model for predicting growth in zinc-deficient stunted infants given supplemental zinc

Recent publication: A dynamic model for predicting growth in zinc-deficient stunted infants given supplemental zinc

Zinc deficiency limits infant growth and increases susceptibility to infections, which further compromises growth. Zinc supplementation improves the growth of zinc-deficient stunted infants, but the amount, frequency, and duration of zinc supplementation required to restore growth in an individual child is unknown. A dynamic model of zinc metabolism that predicts changes in weight and length of zinc-deficient, stunted infants with dietary zinc would be useful to define effective zinc supplementation regimens.

A model of zinc metabolism was developed using data on zinc kinetics, tissue zinc, and growth requirements for healthy 9 month old infants. The model suggests that frequent, smaller doses (5–10 mg Zn/d) are more effective for increasing growth in stunted, zinc-deficient 9-mo-old infants than are larger, less-frequent doses.

In the future, the model predictions of zinc supplementation need to be evaluated in homogenous groups of stunted infants with respect to age, sex, and zinc status. That information will improve predicted amounts of supplemental zinc, and it will identify the population subgroups (e.g., infants with plasma zinc and length-for-age z score below defined thresholds) most likely to respond to zinc supplementation.

The publication can be found here.

Study in progress: Reference methods for biological sample preparation and zinc analysis

Study in progress: Reference methods for biological sample preparation and zinc analysis

The accurate determination of the prevalence of zinc deficiency is essential for effective design, targeting, and evaluation of interventions. Hence, methodological knowledge gaps are important to understand and address.

The concentration of zinc in biological samples, such as plasma, serum, hair, or urine, varies considerably between populations. While part of this variation is attributable to differences in diet or inflammation – i.e. what we want to measure – part may also be due to the different methods and equipment used to process and analyze the samples. 

Instruments commonly used for zinc analysis include atomic absorption spectrometry (AAS), inductively couple plasma optical (atomic) emission spectrometry (ICP-OES / ICP-AES), and ICP mass spectrometry (ICP-MS). 

IZiNCG has earlier published reference methods for collecting plasma and serum for zinc analysis, but reference methods for sample preparation and zinc analysis have not yet been developed. 

The goals of this project are to:

a)    Establish a set of reference methods for zinc analysis, applicable to new or established laboratories using each major type of instrument; and 

b)    Develop reference data that document analytical accuracy and precision among different instruments and different types of samples under ideal conditions at multiple sites. 

The results, anticipated early-mid 2019, will be communicated as an IZiNCG technical brief following publication in a peer-reviewed scientific journal.

Participating labs:

AAS

University of Colorado Denver, USA

ETH Zurich, Switzerland

Aga Khan University, Pakistan

International Centre for Diarrhoeal Disease Research, Bangladesh

National Institute of Nutrition, Hanoi, Vietnam

ICP-OES

Children’s Hospital Oakland Research Institute, USA

ICP-MS

University of Colorado, Denver, USA

ETH Zurich, Switzerland

Oklahoma State University, USA

Which form? How much? How often?

Which form? How much? How often?

Multiple Micronutrient Powder (MNP) programs are being scaled up globally and present a golden opportunity for delivering preventive zinc to older infants and young children.