Biofortification: A review of ex-ante models

Transforming Nigerian Food Systems Through Their Backbones: Lessons From a Decade of Staple Crop Biofortification Programing

This article presents the evolution of the biofortification program in Nigeria over the last decade and the role of interdisciplinary research in informing cost-effective, efficient, and inclusive development; implementation; and scaling of this program. Launched in 2011 to improve Nigeria's food systems to deliver accessible and affordable nutrients through commonly consumed staples, the Nigeria biofortification program was implemented through an effective partnership between the CGIAR and public, private, and civil society sectors at federal, state, and local levels. By the end of 2021, several biofortified varieties of Nigeria's 2 main staples, namely cassava and maize, were officially released for production by smallholders, with several biofortified varieties of other key staples (including pearl millet, rice, and sorghum) either under testing or in the release pipeline. In 2021, the program was estimated to benefit 13 million Nigerians consuming biofortified cassava and maize varieties. The evidence on the nutritional impact, consumer and farmer acceptance, and cost-effective scalability of biofortified crops documented by the program resulted in the integration of biofortified crops in several key national public policies and social protection programs; private seed and food company products/investments, as well as in humanitarian aid.

Role of socio-economic research in developing, delivering and scaling new crop varieties: the case of staple crop biofortification

The CGIAR biofortification program, HarvestPlus, was founded with the aim of improving the quality of diets through micronutrient-dense varieties of staple food crops. Implemented in four phases - discovery, development, delivery and scaling - the program was designed to be interdisciplinary, with plant breeding R&D supported by nutrition and socio-economic research. This paper explains the need, use and usefulness of socio-economic research in each phase of the program. Ex ante and ex post benefit-cost analyses facilitated fundraising for initial biofortification R&D and implementation in each subsequent phase, as well as encouraged other public, private, and civil society and non-governmental organizations to take on and mainstream biofortification in their crop R&D, policies, and programs. Socio-economics research helped guide plant breeding by identifying priority micronutrient- crop- geography combinations for maximum impact. Health impacts of biofortification could be projected both by using empirical results obtained through randomized controlled bioefficacy trials conducted by nutritionists, and through farmer-adoption models estimating impact at scale. Farmer and consumer surveys and monitoring systems provided the underlying information for estimating farmer adoption models and helped understand input/output markets, farmer and consumer preferences, and additional opportunities and challenges -all of which informed crop breeding and delivery activities, while building the knowledge base for catalyzing the scaling of biofortification.

Breeding and adoption of biofortified crops and their nutritional impact on human health

Micronutrient malnutrition has affected over two billion people worldwide and continues to be a health risk. A growing human population, poverty, and the prevalence of low dietary diversity are jointly responsible for malnutrition, particularly in developing nations. Inadequate bioavailability of key micronutrients, such as iron (Fe), zinc (Zn), and vitamin A, can be improved through agronomic and/or genetic interventions. The Consultative Group on International Agricultural Research prioritizes developing biofortified food crops that are rich in minerals and vitamins through the HarvestPlus initiative on biofortification. The objective of this review is to provide an overview of biofortified food crops along with evidence supporting their acceptability and adoption. Between 2004 and 2019, 242 biofortified varieties belonging to 11 major crops were released in 30 countries across Asia, Africa, and Latin America. These conventionally bred biofortified crops include Fe-enriched beans, pearl millet, and cowpea; Zn-enriched rice, wheat, and maize; both Fe- and Zn-enriched lentil and sorghum; and varieties with improved vitamin A in orange-fleshed sweet potato, maize, cassava, and banana/plantain. In addition to ongoing efforts, breeding innovations, such as speed breeding and CRISPR-based gene editing technologies, will be necessary for the next decade to reach two billion people with biofortified crops.

Zinc-biofortified staple food crops to improve zinc status in humans: a systematic review

Biofortified foods are a new approach to increase minerals in the diet, and evidence suggests that zinc (Zn) biofortification can improve Zn physiological status in humans. This systematic review aimed to answer the question: "What are the effects of the consumption of Zn biofortified foods on Zn status in humans?". This review was conducted according to PRISMA guidelines and registered in PROSPERO (CRD42021250566). PubMed, Cochrane, Scopus and Science Direct databases were searched for studies that evaluated the effects of Zn biofortified foods on Zn absorption. Of 4282 articles identified, nine remained after inclusion/exclusion criteria were applied. Limitations in study quality, external and internal validity (bias/confounding), and study power were evaluated. The Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) was used to assess the certainty of evidence. Of the nine articles included, five observed an increase in total Zn absorption, and one showed that Zn participated in the conversion of linoleic acid to dihomo-γ-linolenic acid. By increasing the amount of Zn in the food, Zn biofortification can reduce the phytate:Zn molar ratio and improve Zn absorption in humans. More studies are needed to clarify what portion of Zn biofortified foods/day is needed to achieve a significant effect on Zn status.

Agronomic biofortification of cowpea with zinc: Variation in primary metabolism responses and grain nutritional quality among 29 diverse genotypes

Dietary zinc (Zn) deficiency is widespread globally, and is particularly prevalent in low- and middle-income countries (LMICs). Cowpea (Vigna unguiculata (L.) Walp) is consumed widely in LMICs due to its high protein content, and has potential for use in agronomic biofortification strategies using Zn. This study aimed to evaluate the effect of Zn biofortification on grain nutritional quality of 29 cowpea genotypes. Zn application did not increase cowpea yield. In 11 genotypes sucrose concentration, in 12 genotypes total sugar concentration, and in 27 genotypes storage protein concentration increased in response to Zn supply. Fifteen genotypes had lower concentrations of amino acids under Zn application, which are likely to have been converted into storage proteins, mostly comprised of albumin. Phytic acid (PA) concentration and PA/Zn molar ratio were decreased under Zn application. Six genotypes increased shoot ureides concentration in response to Zn fertilization, indicating potential improvements to biological nitrogen fixation. This study provides valuable information on the potential for Zn application to increase cowpea grain nutritional quality by increasing Zn and soluble storage protein and decreasing PA concentration. These results might be useful for future breeding programs aiming to increase cowpea grain Zn concentrations through biofortification.

The impact of food fortification on stunting in Zimbabwe: does gender of the household head matter?

Background

High prevalence of stunting in children under 5 years poses a major threat to child development in developing countries. It is associated with micronutrient deficiency arising from poor diets fed to children under 5 years. Food fortification is amongst the interventions focused at reducing the incidence of stunting in children under 5 years.

Methods

Using a large-scale household data from Zimbabwe, we investigated the gender-based importance of household adoption of food fortification on the proportion of stunted children in the household. We employed propensity score matching to mitigate self-selection bias associated with household adoption of food fortification.

Results

We offer three major findings. Firstly, we find statistically weak evidence that female headed households are more likely to adopt food fortification than their male counterparts. Secondly, food fortification reduces the proportion of stunted children in the household. Finally, in comparison to non-adopters, female headed households that adopt food fortification are more able to reduce the proportion of stunted children in their households than their male counterparts.

Conclusion

The results highlight the need for policy makers to actively promote food fortification, as such interventions are likely to contribute to the reduction of stunting and to involve men in fortification interventions to improve on their knowledge and appreciation of fortified foods and the associated benefits.