The Impact of Consuming Zinc-Biofortified Wheat Flour on Haematological Indices of Zinc and Iron Status in Adolescent Girls in Rural Pakistan: A Cluster-Randomised, Double-Blind, Controlled Effectiveness Trial

The Effectiveness of Zinc-Biofortified Wheat Flour Intake on the Growth and Morbidity Outcomes of Rural Pakistani Children and Adolescent Girls: A Cluster-Randomised, Double-Blind, Controlled Trial

BACKGROUND

Zinc-biofortified cereals are a promising strategy to combat zinc deficiency, though evidence on health outcomes is limited. This study assessed the effectiveness of consuming zinc-biofortified wheat flour on growth and zinc-related morbidity among adolescent girls (10-16 years; N = 517) and children (1-5 years; N = 517) living in rural north-west Pakistan.

METHODS

In this double-blind, cluster-randomised controlled effectiveness trial, 486 households received either zinc-biofortified or control wheat flour for 25 weeks. Anthropometric measurements and lung function tests (LFTs) were performed at the beginning, middle, and endline. Data on the incidence and duration of respiratory tract infection (RTI) and diarrhoea in the preceding two weeks were collected fortnightly. Analyses included baseline-adjusted linear mixed models for continuous outcomes and Pearson's chi-square for categorical data.

RESULTS

At a zinc differential of 3.7 mg/kg for adolescent girls provided by zinc-biofortified wheat flour, the intervention had no significant effect on height or weight. For children, head circumference was significantly greater in the biofortified group at endline (control 48.47 ± 2.03 cm vs. intervention 48.76 ± 1.82 cm; p = 0.003), with no differences in other anthropometric parameters. Towards the end of the trial, a lower incidence of RTIs was reported in the intervention arm compared to the control arm for both children (week 26: control 27.4% vs. intervention 17.6%, p = 0.036) and adolescent girls (week 24: control 19.3% vs. intervention 11.5%, p = 0.037; week 26: control 14.5% vs. intervention 6.1%, p = 0.014). When the longitudinal prevalence (cumulative days of sickness as a percentage of total days) of RTI was considered, no treatment effects were observed. No benefits of treatment were reported for diarrhoea or LFT.

CONCLUSIONS

The provision of zinc-biofortified wheat flour for 25 weeks did not have a significant effect on the growth of adolescent girls but modestly improved head circumference in children. Longer-term interventions are needed to monitor changes in functional outcomes with the national scale-up of zinc-biofortified wheat varieties.

Das J. Biofortification and fortification of wheat flour: Qualitative analysis for implementation and acceptance

This paper comprehensively investigates various aspects of dietary behaviors relating to the usage of wheat flour and sociocultural preferences embedded within rural communities and aims to bridge health gaps resulting from zinc deficiency by introducing zinc bio-fortified and fortified flour in Pakistan. A household and a market study was conducted in Ghotki and Tando Muhammad Khan districts in Sindh, Pakistan. Various stakeholders involved in the wheat-flour industry including farmers, seed suppliers, owners of atta-chakkis and flour mills, grocers and flour merchants, bakers and hoteliers, consumers, and agronomists were interviewed to gauge their knowledge of bio-fortified and fortified wheat-flour. Wheat-flour is a staple food item in Pakistan, however, agricultural output in Pakistan varies across all provinces. Factors that hinder agricultural productivity include a shortfall of essential resources such as irrigation water, superior quality seeds and fertilizers, and machinery. Farmers use primitive methods of farming as they do not have access to modern technologies, information, or training. Wheat flour market vendors and consumers lack awareness of bio-fortified and fortified wheat flour products and believe the only way to create a customer-base is by ensuring that fortified wheat products are available to all and competitively priced compared to traditional options. Additionally, participants misconstrue the process of fermentation and perceive it as unhealthy. The lack of financial resources and awareness restricts adequate promotion of nutrient-rich food products amongst stakeholders involved in the wheat flour industry. Mass awareness campaigns, education and government incentives could bridge the gaps present and encourage wider adoption of bio-fortified and fortified wheat flour. Policy makers and communities can draw on the recommendations made in this paper to introduce and promote zinc bio-fortified and zinc-fortified flour in settings where zinc deficiency is prevalent.

Editorial

Nutritional requirements of individuals vary across the lifecycle, according to activity, age and gender. To optimize human health, consideration of nutritional priorities at each stage is needed. This conference brought together multidisciplinary experts in maternal and child nutrition and health, cardiometabolic and plant-based nutrition and dietitians involved in the care of vulnerable populations, plus nutritional metabolism, health and ageing. The presentations highlighted the most important nutrition research in these areas, updating knowledge and suggesting how dietary advice and policy could be adapted to incorporate research findings. With the global increase in non-communicable disease (NCD) and nutrition being considered as a key modifiable risk factor for the prevention and management of NCD, this conference was much needed.

Fortification or biofortification: complimentary strategies or duplication of effort?

Micronutrient deficiencies continue to be a global concern, with the most common deficiencies being vitamin A, iron, zinc and B vitamins (folate and B12). Addressing this requires strategies that are scalable and equitable such that they reach all members of a population irrespective of socioeconomic status and geography. Fortification and biofortification offer potential large-scale solutions, however each have strengths and limitations depending on the context, particularly the cultural and political factors that may create barriers or opportunities for effectiveness. Planning how to target scarce resources for maximum impact requires an in-depth knowledge and understanding of local food systems and market dynamics, alongside strong government policy and legislative support. A food fortification programme was launched in Pakistan in 2016, supported by UK Aid and designed to address the high prevalence of vitamin A, iron and zinc deficiency, particularly in women and children. In the same year, the first zinc biofortified variety of wheat, Zincol-2016, was released in Pakistan, supported and developed through the HarvestPlus programme in collaboration with the Pakistan National Agriculture Research Centre. This review explores the challenges faced by fortification and biofortification, initiated independently, (but around the same time) in Pakistan.

Zinc-Biofortified Rice Improves Growth in Zinc-Deficient Rats

Biofortification of staple food crops with zinc (Zn) is considered a sustainable strategy to prevent deficiency, but evidence on their health impact is awaited. The weaning Wistar/Kyoto male rats were fed on a Zn-deficient diet (ZDD, < 0.1 ppm) for 4 weeks followed by repletion (pair feeding) with control rice diet without (CRD; 5.0 ± 0.23 ppm) or with additional Zn (CRD + Zn, 30.3 ± 0.60 ppm) or biofortified rice diet (BRD; 8.54 ± 0.51 ppm) for 3 weeks. Body weights, plasma, liver, pancreatic, fecal Zn levels, and intestinal ZIP4 and ZnT1 mRNA expression were measured at the end of the experiment. The body weight of rats fed on CRD or CRD + Zn or BRD significantly increased (p < 0.01) compared to rats fed on ZDD. The body weight BRD was significantly higher compared to CRD (P < 0.01), both of which remained lower compared to CRD + Zn (p < 0.03). Repletion of Zn through either CRD or BRD significantly increased the plasma Zn concentration (PZC), tissue, and fecal Zn excretion compared to ZDD, without significant between-group differences. However, PZC, tissue, and fecal Zn of CRD + Zn was significantly higher compared to the rest of the groups. The intestinal ZIP4 and ZnT1 mRNA expressions are consistent with Zn status and/or dietary Zn exposure. A similar PZC, tissue, and fecal Zn in CRD compared to BRD, despite higher Zn intakes in the latter, could be due to preferential shuttling of Zn for growth. Together, these results indicate that Zn from biofortified rice is efficiently utilized for promoting the growth in Zn-deficient rats.

Effects of Zinc-Biofortified Wheat Intake on Plasma Markers of Fatty Acid Metabolism and Oxidative Stress Among Adolescents

BACKGROUND/OBJECTIVE

Zinc deficiency is common worldwide and has been linked to reduced growth and immune function, increased risk of and slower recovery from infections, and increased risk of non-communicable diseases. To address the issue, zinc biofortification of wheat has been proposed as a sustainable approach to increase dietary zinc intake in countries like Pakistan, where zinc deficiency rates are high and wheat is the primary staple crop. Since plasma zinc concentration (PZC) does not reliably respond to small changes in zinc intake, biomarkers sensitive to small changes in zinc intake achievable though biofortification are needed. Activity indices for zinc-dependent metabolic steps of desaturation and elongation of omega-6 fatty acids (FAs) have been proposed as sensitive zinc biomarkers. Oxylipin metabolites of polyunsaturated FAs may also respond to changes in zinc intake and further mediate metabolic response to oxidative stress. The objective of the current study was to assess the effects of consuming zinc-biofortified wheat flour on plasma markers of fatty acid (FA) metabolism in females aged 10-16 years.

METHODS

A nested secondary analysis was conducted in samples from a double-blind, cluster-randomized controlled trial conducted in rural Pakistan, whereparticipants (n = 517) consumed either zinc-biofortified wheat flour or control flour for 25 weeks. Total plasma FAs and oxylipins were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS). Activity indices were estimated from the ratios of product to precursor FAs.

RESULTS

Except for docosahexaenoic acid (DHA, p < 0.05), no significant intervention effect was observed on plasma FAs and FA activity index endpoints. Zinc-biofortified wheat intake reduced pro-inflammatory oxylipins and biomarkers of oxidative stress, 5-HETE (p < 0.05), 9-HETE (p < 0.05), 11-HETE (p < 0.05), and 15-HETE (p < 0.05), compared with the control. However, after adjustment for multiple comparisons, none of the intervention effects remained significant.

CONCLUSIONS

Further study of the responsiveness and specificity of plasma oxylipins to changes in zinc intake is warranted.

Monitoring Biofortification Program Performance and Potential for Impact: Indicators, Methods, and Learnings from the Commercialization of Biofortified Crops Program in Six Countries across Africa and Asia

Background

Biofortification of staple crops is a food-based strategy to reduce the high global burden of micronutrient deficiencies. Monitoring program performance is essential to ensure biofortification programs have high potential for impact; however, few indicators and methods for doing so are publicly available.

Objective

We documented the set of standardized indicators and methods used to monitor the Commercialization of Biofortified Crops (CBC) program and reviewed their strengths and limitations.

Methods

Following the CBC program impact pathway, we identified and defined a set of indicators and corresponding methods. Country-level implementation teams contextualized and operationalized them to monitor 9 country-crop programs (i.e., high iron beans in Kenya and Tanzania, iron pearl millet in India, vitamin A maize in Nigeria and Tanzania, vitamin A cassava in Nigeria, zinc wheat in Pakistan and India, and zinc rice in Bangladesh) from 2020 to 2022.

Results

Twenty indicators were defined across domains of seed supply, production, availability, awareness, capacity development, advocacy, and consumption of biofortified foods. Data collection methods included external and internal document review, farmer household surveys, rapid market assessments, and modeling. The strengths of these methods were that they were rapid to conduct, low cost, and simple to use. For some methods, the limitations were the potentially reduced accuracy of some results due to the use of external data sources or secondary data inputs and unavailability of data.

Conclusions

The indicators and methods used in the CBC program are practical and cost effective for monitoring the implementation of biofortification programs because they generate the range of information necessary to understand how effectively a program is delivered and bolster plausibility arguments for attributing observed impacts to program activities. Further testing is needed to confirm their generalizability when applied to different contexts and paired with impact evaluations with the aim of producing publicly available global guidance documents.

Nutritional status of school-age children (5-19 years) in South Asia: A scoping review

Information on malnutrition for school-age children and adolescents (5-19 years) in South Asia is fragmented and inconsistent, which limits the prioritization of nutrition policies, programmes and research for this age group. This scoping review aimed to synthesize existing evidence on the burden of malnutrition for children and adolescents aged 5-19 years in South Asia, and on interventions to improve their nutritional status. Cochrane Library, EMBASE, Medline and Google Scholar were systematically searched for articles published between January 2016 and November 2022. Eligible studies reported the prevalence of undernutrition, overweight/obesity, micronutrient deficiencies and unhealthy dietary intakes, and interventions that aimed to address these in South Asia. In total, 296 articles met our inclusion criteria. Evidence revealed widespread, yet heterogeneous, prevalence of undernutrition among South Asian children and adolescents: thinness (1.9%-88.8%), wasting (3%-48%), underweight (9.5%-84.4%) and stunting (3.7%-71.7%). A triple burden of malnutrition was evident: the prevalence of overweight and obesity ranged from 0.2% to 73% and 0% to 38% (with rapidly rising trends), respectively, alongside persistent micronutrient deficiencies. Diets often failed to meet nutritional requirements and high levels of fast-food consumption were reported. Education, fortification, supplementation and school feeding programmes demonstrated beneficial effects on nutritional status. Comprehensive and regular monitoring of all forms of malnutrition among children and adolescents, across all countries in South Asia is required. Further, more large-scale intervention research is needed to ensure policy and programmes effectively target and address malnutrition among children and adolescents in South Asia.

Root system architecture associated zinc variability in wheat (Triticum aestivum L.)

Root system architecture (RSA) plays a fundamental role in nutrient uptake, including zinc (Zn). Wheat grains are inheritably low in Zn. As Zn is an essential nutrient for plants, improving its uptake will not only improve their growth and yield but also the nutritional quality of staple grains. A rhizobox study followed by a pot study was conducted to evaluate Zn variability with respect to RSA and its impact on grain Zn concentration. The grain Zn content of one hundred wheat varieties was determined and grown in rhizoboxes with differential Zn (no Zn and 0.05 mg L-1 ZnSO4). Seedlings were harvested 12 days after sowing, and root images were taken and analyzed by SmartRoot software. Using principal component analysis, twelve varieties were screened out based on vigorous and weaker RSA with high and low grain Zn content. The screened varieties were grown in pots with (11 mg ZnSO4 kg-1 soil) and without Zn application to the soil. Zinc translocation, localization, and agronomic parameters were recorded after harvesting at maturity. In the rhizobox experiment, 4% and 8% varieties showed higher grain Zn content with vigorous and weaker RSA, respectively, while 45% and 43% varieties had lower grain Zn content with vigorous and weaker RSA. However, the pot experiment revealed that varieties with vigorous root system led to higher grain yield, though the grain Zn concentration were variable, while all varieties with weaker root system had lower yield as well as grain Zn concentration. Zincol-16 revealed the highest Zn concentration (28.07 mg kg-1) and grain weight (47.9 g). Comparatively higher level of Zn was localized in the aleurone layer than in the embryonic region and endosperm. It is concluded that genetic variability exists among wheat varieties for RSA and grain Zn content, with a significant correlation. Therefore, RSA attributes are promising targets for the Zn biofortification breeding program. However, Zn localization in endosperm needs to be further investigated to achieve the goal of reducing Zn malnutrition.

Farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan: a mixed methods study

Background

Zinc biofortified wheat may be a sustainable strategy to increase zinc intake in areas where fortification and dietary diversification are not feasible or are limited by household purchasing power. This convergent mixed methods study aimed to explore the farmers' and millers' experiences and attitudes towards the production and processing of zinc biofortified wheat in Pakistan.

Methods

A telephone survey was conducted with farmers (n = 418) who were provided with Zincol-2016 biofortified wheat seed for the 2019-2020 growing season, as part of a wheat grain micronutrient mapping study across Punjab Province. The survey explored the farmers' experiences of growing Zincol-2016 and whether they opted to grow it again in the subsequent season. Semi-structured focus group discussions were undertaken in a separate group of farmers in Khyber Pakhtunkhwa (KP) province (n = 12) who grew Zincol-2016 for the BiZiFED2 RCT. Millers were also interviewed in KP, both those who had processed Zincol-2016 for the trial (n = 12) and those who had no experience of processing biofortified wheat (n = 12). Survey data were analyzed using descriptive statistics and transcripts of focus groups were analyzed using thematic analysis.

Results

Nearly half of farmers who responded to the survey (47%) re-cultivated Zincol-2016 in the following season. The drivers for Zincol-2016 re-cultivation were seed availability (100%), grain yield and growth resistance (98%), quality of the flour from the previous harvest (97%) and nutritional benefit (94.5%). Discussions with farmers suggested that the main motivators for potential scale-up of biofortified wheat were the perceived quality of the grain, wheat, and flour. Millers saw it as an opportunity to expand their business. Farmers and millers valued the health benefits of the wheat. Challenges for scale-up include the need of additional support to produce it, unfamiliarity with the biofortification process, production costs, and external threats to the supply chain.

Conclusion

Farmers and millers showed a strong implicit preference for Zincol-2016 over alternative varieties. Crop performance and product yield were the most cited motivators for growing Zincol-2016. Farmers and millers are willing to produce and process biofortified wheat if financial and educational support is provided.

The Effect of Zinc Biofortified Wheat Produced via Foliar Application on Zinc Status: A Randomized, Controlled Trial in Indian Children

BACKGROUND

Agronomic zinc biofortification of wheat by foliar application increases wheat zinc content and total zinc absorption in humans.

OBJECTIVES

To assess the effect of agronomically biofortified whole wheat flour (BFW) on plasma zinc (PZC) compared with a postharvest fortified wheat (PHFW) and unfortified control wheat (CW) when integrated in a midday school meal scheme.

METHODS

We conducted a 20-wk double-blind intervention trial in children (4-12 y, n = 273) individually randomly assigned to 3 groups to receive a daily school lunch consisting of 3 chapattis prepared with the 3 different wheat flour types. Measurements of anthropometry, blood biochemistry, and leukocyte DNA strand breaks were conducted. We applied sparse serial sampling to monitor PZC over time, and analysis was performed using linear mixed-effects models.

RESULTS

Mean zinc content in BFW, PHFW, and CW were 48.0, 45.1, and 21.2 ppm, respectively (P < 0.001). Mean (standard deviation) daily zinc intakes in the study intervention in BFW, PHFW, and CW groups were 4.4 (1.6), 5.9 (1.9) and 2.6 (0.6) mg Zn/d, respectively, with intake in groups PHFW and BFW differing from CW (P < 0.001) but no difference between BFW and PHFW. There were no time effect, group difference, or group × time interaction in PZC. Prevalence of zinc deficiency decreased in the BFW (from 14.1%-11.2%), PHFW (from 8.9%-2.3%), and CW (9.8%-8.8%) groups, but there was no time × treatment interaction in the prevalence of zinc deficiency (P = 0.191). Compliance with consuming the study school meals was associated with PZC (P = 0.006). DNA strand breaks were not significantly associated with PZC (n = 51; r = 0.004, P = 0.945).

CONCLUSIONS

Consumption of either PHFW or BFW provided an additional ∼1.8 to 3.3 mg Zn/d, but it did not affect PZC or zinc deficiency, growth, or DNA strand breaks. This trial was registered on clinicaltrials.gov as NCT02241330 and ctri.nic.in as CTRI/2015/06/005913.

Single hair analysis by X-ray fluorescence spectrometry detects small changes in dietary zinc intake: A nested randomized controlled trial

The aim of this study was to determine whether X-ray fluorescence spectrometry (XRF) could be used to detect changes in hair zinc concentration in response to a modest daily increase in zinc from the consumption of zinc biofortified wheat flour. This study was conducted as part of an effectiveness trial (BiZiFED2) exploring the potential for zinc biofortified wheat to alleviate zinc deficiency in adolescent girls aged 10-16 years in Pakistan (trial registration ID ISRCTN17107812). A randomized controlled design was used. Participants received either control flour or zinc biofortified flour for 6 months. Consumption of biofortified flour resulted in an average daily increase in dietary zinc intake of 1.5 mg per day above that of the control flour. At baseline and at the end of the intervention, individual hair samples (control: n = 59, intervention: n = 64) were analyzed for zinc and sulfur content by XRF. Data were analyzed using linear mixed effects models to contrast between trial groups the changes from baseline to end point and also to compare baseline and end point values within each trial group. Increases from baseline to endpoint in both sulfur and zinc were significantly greater in the intervention group compared to control (sulfur counts.

CONTROL

baseline = 119.87 ± 20.33 and endpoint = 121.58 ± 23.58/intervention: baseline = 122.67 ± 24.19 and endpoint = 131.60 ± 21.34); (Zinc counts.

CONTROL

baseline = 50.88 ± 14.33 and endpoint = 54.82 ± 14.61/intervention: baseline = 49.61 ± 10.77 and endpoint = 58.79 ± 12.20). For these parameters, there were also significant increases from baseline to endpoint in the intervention group but not in control. Furthermore, for Zn:S count ratio there were no differences in terms of the magnitude of the change from baseline to endpoint in the control group, although significant increases from baseline to endpoint were evident in the intervention group (Zn:S count ratio.

CONTROL

baseline = 0.42 ± 0.10 and endpoint = 0.45 ± 0.08/intervention: baseline = 0.41 ± 0.08 and endpoint = 0.45 ± 0.08). A modest increase in dietary zinc over 6 months resulted in a detectable increase in both sulfur and zinc counts in individual hairs measured using XRF. This offers a sensitive, non-invasive method to monitor changes within subjects in response to dietary zinc interventions.

Zinc agronomic biofortification of staple crops may be a cost-effective strategy to alleviate zinc deficiency in Ethiopia

BACKGROUND

Inadequate dietary zinc (Zn) supplies and Zn deficiency (ZnD) are prevalent in Ethiopia, where cereals are major dietary sources, yet low in bioavailable Zn. Zinc agronomic biofortification (ZAB) of staple crops through application of Zn fertilizers may contribute to alleviating ZnD. However, large-scale promotion and adoption of ZAB requires evidence of the feasibility and public health benefits. This paper aimed to quantify the potential cost-effectiveness of ZAB of staple crops for alleviating ZnD in Ethiopia.

METHODS

Current burden of ZnD among children in Ethiopia was quantified using a disability-adjusted life years (DALYs) framework. Evidence on baseline dietary Zn intake, cereal consumption, and fertilizer response ratio was compiled from existing literature and secondary data sources. Reduction in the burden of ZnD attributable to ZAB of three staple cereals (maize, teff, and wheat) via granular and foliar Zn fertilizer applications was calculated under optimistic and pessimistic scenarios. The associated costs for fertilizer, labor, and equipment were estimated in proportion to the cropping area and compared against DALYs saved and the national Gross Domestic Product capita-1.

RESULTS

An estimated 0.55 million DALYs are lost annually due to ZnD, mainly due to ZnD-related mortality (91%). The ZAB of staple cereals via granular Zn fertilizer could reduce the burden of ZnD by 29 and 38% under pessimistic and optimistic scenarios, respectively; the respective values for ZAB via foliar application were 32 and 40%. The ZAB of staple cereals via granular fertilizer costs US$502 and US$505 to avert each DALY lost under optimistic and pessimistic scenarios, respectively; the respective values for ZAB via foliar application were US$226 and US$ 496. Foliar Zn application in combination with existing pesticide use could reduce costs to US$260-353 for each DALY saved. Overall, ZAB of teff and wheat were found to be more cost-effective in addressing ZnD compared to maize, which is less responsive to Zn fertilizer.

CONCLUSION

ZAB of staple crops via granular or foliar applications could be a cost-effective strategy to address ZnD, which can be integrated with the existing fertilizer scheme and pesticide use to minimize the associated costs.