Biofortified Wheat Increases Dietary Zinc Intake: A Randomised Controlled Efficacy Study of Zincol-2016 in Rural Pakistan

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.

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.

Existing knowledge on Zn status biomarkers (1963-2021) with a particular focus on FADS1 and FADS2 diagnostic performance and recommendations for further research

The role of Zn in human health was discovered 60 years ago, and despite remarkable research efforts, a sufficiently sensitive and specific biomarker of Zn status is still lacking. Plasma/serum Zn, currently the best available and most accepted population Zn status indicator, responds well to severe Zn deficiency, yet, mild to moderate Zn deficiency states usually remain unrecognized. Identifying early-stage Zn deficiency requires additional robust markers of Zn status. This paper discusses the sensitivity, specificity, and responsiveness of plasma Zn concentrations to Zn interventions. It describes the biochemical and dietary basis for the causal association between Zn and fatty acid desaturases activity, FADS1 and FADS2, based on data collected through studies performed in animals and/or humans. The influence of potential confounders and covariates on the observed relationships is considered. Additional potential Zn biomarkers are discussed and suggestions for further research in this area are provided.

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.

Role of Nutrition Information in Acceptance and Willingness to Pay for Biofortified Cereal Food: Implications for Better Health and Sustainable Diet

A range of nutritional needs are met through the use of fortified farm-based foods. Wheat biorfortification with zinc is such an example where biorfortification is carried out for a crucial element like Zinc. Zinc-biofortified wheat (Zn-wheat) has been officially launched in Pakistan since 2016 but its wide-scale dissemination, adoption and consumption have not taken place till to date. On the other hand, essential nutrients deficiencies have wide-ranging implications for public health especially for children and lactating mothers. This study is undertaken to know the reasons for the slow progression of scaling up of biofortified wheat varieties in Pakistan, people’s awareness about biofortified wheat and to recognize the role of information in acceptance and willingness to pay for this wheat. For this purpose, randomly selected 474 households were interviewed from four districts of Punjab province. They were categorized into four groups based on their exposure to information in real and hypothetical cheap talk (game theory context). Study findings reveal that respondents were ready to pay for fortified wheat if they are aware about nutrient aspects and Zn deficiency. Using Discrete Choice Experiment, the preferences for and factors affecting the willingness to pay for fortified wheat are evaluated. Main factors having positive impact include household head’s education and income, having pregnant women and children <5 years age. It was also found that people having valid information about nutrients of a food would be willing to pay more. The study highlights need for policy focus on educating people about nutritional aspects as well as making available biofortified foods to promote healthy living.

FADS1 and FADS2 as biomarkers of Zn status - a systematic review and meta-analysis

Despite enormous research efforts, a sufficiently sensitive and reliable biomarker for the assessment of zinc (Zn) status has not been identified to date. Zn affects fatty acid metabolism and alters the activity of certain desaturases; thus, desaturase activity has been proposed as a potential new biomarker of Zn status. This systematic review complied and assessed studies that examined changes in fatty acid desaturase 1 (FADS1) and fatty acid desaturase 2 (FADS2) activities in relation to modifications in dietary Zn intake. A systematic search was performed in PubMed, Web of Science, Scopus, Web of Knowledge, and Central with strictly defined search, inclusion, and exclusion criteria. Twenty-one studies were included, 8 animal and 13 human trials (5 randomized controlled trials, two non-randomized controlled trials, and 6 cross-sectional studies). This systematic review was performed using PRISMA guidelines and where feasible a random-effects meta-analysis was conducted. No significant correlation was seen between the delta 6 desaturase and Zn status (-0.0958, 95% CIs (-0.2912; 0.1074), p = 0.2928). Delta 6 desaturase seems to respond in a greater magnitude than Zn status to Zn-containing interventions (the standardized mean difference for delta 6 desaturase was -0.6052, 95% CIs (-2.7162; 1.5058), p = 0.4289, while for plasma/serum Zn it was 0.0319, 95% CIs (-0.9133; 0.9770), p = 0.9213). Finally, two separate meta-analyses on same studies that assessed the correlations between LA:DGLA and Zn intake and Zn status and Zn intake revealed that the magnitude of correlations was only slightly different (the pooled correlation coefficient between the LA:DGLA ratio and Zn intake had a value of -0.1050, 95% CIs (-0.5356; 0.3690), p = 0.454, while between plasma Zn and Zn intake had a value of -0.0647, 95% CIs (-0.4224; 0.3106), p = 0.5453). According to the descriptive analysis, the magnitude of variation in desaturase activities in response to Zn intake was not consistent among studies, FADS1 and FADS2 activity corresponded to dietary Zn manipulations, both in animals and humans. A plausible explanation for this observation might be the difference between the studies in study populations, types of dietary interventions, study durations, etc. In addition, several potential confounders and covariates are identified from the qualitative synthesis, such as gender, age, the type of fat provided within the dietary intervention, the size of Zn particles, among others. Further high-quality studies are needed to additionally clarify the suggested associations and applicability of utilizing fatty acid desaturase activities as Zn status biomarkers.

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

Biofortification of wheat is potentially a sustainable strategy to improve zinc intake; however, evidence of its effectiveness is needed. A household-based, double-blind, cluster-randomized controlled trial (RCT) was conducted in rural Pakistan. The primary objective was to examine the effects of consuming zinc-biofortified wheat flour on the zinc status of adolescent girls aged 10−16 years (n = 517). Households received either zinc-biofortified flour or control flour for 25 weeks; blood samples and 24-h dietary recalls were collected for mineral status and zinc intake assessment. Plasma concentrations of zinc (PZC), selenium and copper were measured via inductively coupled plasma mass spectrometry and serum ferritin (SF), transferrin receptor, alpha 1-acid glycoprotein and C-reactive protein by immunoassay. Consumption of the zinc-biofortified flour resulted in a moderate increase in intakes of zinc (1.5 mg/day) and iron (1.2 mg/day). This had no significant effect on PZC (control 641.6 ± 95.3 µg/L vs. intervention 643.8 ± 106.2 µg/L; p = 0.455), however there was an overall reduction in the rate of storage iron deficiency (SF < 15 µg/L; control 11.8% vs. 1.0% intervention). Consumption of zinc-biofortified flour increased zinc intake (21%) but was not associated with an increase in PZC. Establishing a sensitive biomarker of zinc status is an ongoing priority.

Community Perceptions of Zinc Biofortified Flour during an Intervention Study in Pakistan

Zinc-biofortified flour may be a cost-effective approach to improve zinc status of populations in low-resource settings. The success of biofortification programmes is subject to acceptability and uptake by consumers. This study explored community leaders’ and community members’ (n = 72) experiences and attitudes towards the flour provided during a cluster randomised controlled trial of zinc biofortified wheat in rural Pakistan (BiZiFED2). Focus group discussions (n = 12) were conducted and thematic analysis applied using an inductive, semantic, contextualist approach. Five themes were identified: (1) Contribution to food security; (2) Better sensory and baking properties than local flour; (3) Perceived health benefits; (4) Willingness to pay for the flour; and (5) Importance of trusted promoters/suppliers. Although the participants were blind to whether they had received control or biofortified flour, referred to collectively as “study flour”, the results indicated that the study flour performed well in terms of its taste and bread making qualities, with no adverse reports from participants in either arm of the BIZIFED2 RCT. Participants suggested that they would buy the biofortified wheat if this was available at a fair price due to perceived health benefits, reporting positive sensory characteristics and cooking attributes when compared to the flour available in the local markets. Overall, there was a positive reception of the programme and flour among the participants, and members of the community hoped for its continuation and expansion.