BNFB – Facts on Biofortification

Facts on Biofortification

Biofortification is the process of increasing nutritional value of food crops by increasing the density of vitamins and minerals in a crop through either conventional plant breeding; agronomic practices or biotechnology. Examples of these vitamins and minerals that can be increased through biofortification include provitamin A Carotenoids, zinc and iron.

  • Conventional crop breeding techniques are used to identify varieties with particularly high concentration of desired nutrients. These are cross-bred with varieties with other desirable traits from the target areas (such a virus resistance, drought tolerance, high yielding, taste) to develop biofortified varieties that have high levels of micronutrients (for example, vitamin A, iron or zinc), in addition to other traits desired by farmers and consumers.  This is the most common approach in use in Africa.
  • Agronomic biofortification entails application of minerals such as zinc or iron as foliar or soil applications, drawing on plant management, soil factors, and plant characteristics to get enhanced content of key micronutrients into the edible portion of the plant.
  • Biotechology is where crops lacking any varieties with any of the micronutrient of interest, can be candidates for utilizing genes from other plants, such as beta-carotene, and inserting that trait of interest into a staple crop using techniques of genetic modification.

Biofortification is one solution among many interventions that are needed to solve the complex problem of micronutrient malnutrition. Approaches range from the food-based approaches (such as dietary diversification, nutrition education and biofortification), to implementing food fortification and supplementation programs of essential nutrients such as vitamin A, iodine zinc, and iron; to inclusion of essential Nutrition Actions in national health and nutrition strategies, to incorporating infant and young child-feeding training into community health extension programs and water and sanitation programs.

Among these interventions biofortification is considered one of the most cost-effective interventions for countries to employ in combating micronutrient malnutrition1

Biofortification reaches rural consumers who have limited access to industrially fortified foods, supplementation interventions, and diverse diets. Most rural households already grow and consume staple food crops. Biofortification combines increased micronutrient content with preferred agronomic, quality, and market traits and therefore biofortified varieties will typically match or outperform the usual varieties that farmers grow and consume.  Poor people often get 60-70% of their calories from staple food crops.  Hence, biofortification targets the poorest consumers.  In the long-term, dietary diversification is likely to ensure a balanced diet that includes the necessary micronutrients needed by the rural poor population.

 

Micronutrients are a group of compounds that are needed in small amounts by human bodies for a wide range of essential functions and for proper growth and development (for example, vitamin A, iron, folate, or zinc). Healthy diets contain a balanced and adequate combination of macronutrients (carbohydrates, fats, and protein) and essential micronutrients.

Micronutrient malnutrition or hidden hunger is caused by a chronic or prolonged lack of essential minerals and vitamins required for proper growth and development of the body. Micronutrient malnutrition is a major risk factor for increased incidence of illness and low productivity and in young children, poor growth and even death. Deficiencies in different micronutrients have different effects (Table 1). The Factors that contribute to micronutrient malnutrition include poor diet, increased micronutrient needs during certain life stages, and health problems such as diseases, infections, and parasites.  However, unlike wasting (severe underweight), symptoms of micronutrient malnutrition are not necessarily visible to the naked eye even when they are affecting health—hence, micronutrient malnutrition is referred to as the hidden hunger.

 

Table 1. Major micronutrient deficiencies and their effects

Micronutrient deficietyEffects include
IodineBrain damage in newborns, reduce mental capacity goiter
IronAnemia, impaired motor and cognitive develoment, increased risk of maternal mortality, premature births, low birthweight, low energy
Vitamin ASevere Visual impairement, blidness, increades risk of severe illness and death from common infections such as diarrhea and measles in preschool age children (in preagnant women) night blindness, increased risk of death
ZincWeakended inmune system, more frequent infections , stunting
Sources Allen(2001); Anderson, Kurumbunathan and Zimmermann(2012); de benoist et al. (2008); Micronutient Initiative (2009); Wessels and brown (2012); and WHO(2009;2014a)

Biofortification has the increased nutritional micronutrient content imbedded in the crop being grown. Food fortification increases the nutritional value of foods by adding trace amounts of micronutrients to foods during processing.  

Yes! Scientific evidence suggests that biofortification is an efficacious, cost-effective, and feasible means of alleviating micronutrient deficiency. A growing number of completed efficacy (biological impact under controlled conditions similar to clinical trials) and effectiveness (biological impact in real life) studies show that biofortification works. Effectiveness evidence is available for orange-fleshed sweetpotato (Low et al., 20072; Hotz, Loechl, de Brauw, et al. 20123; Hotz, Loechl, Lubowa, et al. 20124).

Nutritional efficacy has been demonstrated for vitamin A crops (OFSP (van Jaarsveld et al. (20055), maize (Gannon et al. 20146), cassava (Talsma et al. 20147)) and iron crops (bean (J. Haas et al., n.d.8), pearl millet (Finkelstein et al. 20159), rice (J. D. Haas et al. 200510)).

In Uganda for instance, it was demonstrated that biofortification was ‘good value for money’ (cost effective).  In this case, using the orange-fleshed sweetpotato combined with nutrition education at the community level, biofortification cost US$15-$20 per Disability Adjusted Life Year (DALY) saved, which the World Bank considers a highly cost effective intervention (World Bank 199311; HarvestPlus 201012). An assessment of several crops to determine the consequences of vitamin A, iron, and zinc deficiencies on micronutrient malnutrition in two East African countries, one Central African, one West African, South Asia, Southeast Asia and Latin America provides evidence on the effectiveness of biofortification among young children and adults (including pregnant women). The analyses have shown that the percentage reduction in the burden of VAD ranges between 3% and 30% in the case of vitamin A cassava, between 1% and 32% in the case of vitamin A maize, and between 40% and 67% in the case of vitamin A sweetpotato.  

 

Consuming biofortified staple foods results in higher intakes of targeted micronutrients, which depending on the health status of the individual, can result in improved micronutrient status, thus avoiding the negative effects described in Table 1. Biofortification does not treat acute deficiencies, but contributes to the prevention of micronutrient deficiencies, thereby promoting healthy growth and development.

Table 1. Major micronutrient deficiencies and their effects

Micronutrient deficietyEffects include
IodineBrain damage in newborns, reduce mental capacity goiter
IronAnemia, impaired motor and cognitive develoment, increased risk of maternal mortality, premature births, low birthweight, low energy
Vitamin ASevere Visual impairement, blidness, increades risk of severe illness and death from common infections such as diarrhea and measles in preschool age children (in preagnant women) night blindness, increased risk of death
ZincWeakended inmune system, more frequent infections , stunting
Sources Allen(2001); Anderson, Kurumbunathan and Zimmermann(2012); de benoist et al. (2008); Micronutient Initiative (2009); Wessels and brown (2012); and WHO(2009;2014a)

All of the biofortified crops released in Africa to date have been developed using conventional plant breeding, including vitamin A orange-fleshed sweet-potato, maize, and cassava, as well as iron beans. Conventional breeding methods exploit natural variations existing within the crops. Plant breeders identify parent varieties with high vitamin or mineral levels, and then cross varieties over several generations to produce plants that have the desired nutrient and agronomic traits. However, please note biofortification also includes the use of transgenetic technology, which led for example to biofortified Gold Rice, Super Sorghum and vitamin A Bananas. These transgenic crops have not been commercially released yet. Transgenic approaches face regulatory challenges in SSA.

Consuming biofortified foods is most beneficial to groups that are vulnerable to micronutrient deficiencies (such as vitamin A, iron, or zinc), including children, pregnant and breastfeeding women, and those whose diets are limited by low income and/or lack of access to diverse, healthy foods. Children have higher micronutrient requirements than adults, and pregnant women and lactating women much higher needs than non-pregnant, non-lactating women.

Biofortification is not the single or only solution to improving micronutrient intakes. However, it is a cost-effective, food-based approach to improve the nutritional value of foods that are often low or lacking altogether in micronutrients. It is particularly effective when combined with efforts to improve nutritional knowledge and dietary practice at the community level.  It complements efforts to increase dietary diversity and other interventions that address micronutrient deficiencies, such as fortification and supplementation. 

A ‘food basket’ approach supports dietary diversity by making available a variety of biofortified crops to address dietary deficiencies among vulnerable populations. Dietary diversity takes care of nutritional needs while at the same time takes care of various consumer demand/tastes. For instance, in Nigeria, communities in the northern part of the country use maize as the staple in gari and fufu, whereas in the south, the principal ingredient in gari is cassava. Some states in the middle of the country highly consume sweetpotatoes. If the production and consumption of all three biofortified vitamin A crops—yellow cassava, orange maize, and OFSP—are promoted, virtually all areas of the country would have access to a sustainable, frequently consumed source of vitamin A.

The overlap of cropping patterns, consumption trends, and prevalence of micronutrient deficiencies determine target countries and focus crops. The biofortification priority index (BPI), which ranks countries globally based on their production and consumption of priority crops and the rate of micronutrient deficiency among the target population, is one tool that can be used to understand this overlap. The BPI identifies Tanzania and Nigeria as top priority countries for their target crops.

The Global Nutrition Report of 201413 highlights the magnitude of vitamin A and iron deficiency in Nigeria and Tanzania. These countries also produce and consume staple crops that can be biofortified for increased vitamin A and iron content. When the prevalence of VAD is at least 15%, it is considered a major public health problem.   Therefore, Nigeria and Tanzania are appropriate intervention countries for BNFB. 

Table 2. Status of micronutrient deficiency, prevalence of under-5 stunting, and vitamin A supplementation coverage in Nigeria and Tanzania14

 

Country

 

 Micronutrient Status of the Population (%)

Prevalence of Under-5 Stunting (%)

Intervention Coverage (%) Vitamin A Supplementation

 

 

VAD in Preschool Age Children

 

Iron Deficiency (women of reproductive age with anemia)

Nigeria

 

30

49

36

78

 

Tanzania

 

24

40

35

95

 

          

 

Compiled from: 2014 Nutrition Country Profiles (IFPRI)12

 

 

Biofortified seeds and propagation materials are made available through extension programmes, market mechanisms or by programmes targeting nutritionally vulnerable communities and smallholder farmers.  To find the location of quality planting material with trained vine multipliers or national research programs, refer to the Sweetpotato Knowledge Portal (www.sweetpotatoknowledge.org)

The nutritional value of foods changes with processing and cooking, and vitamin A is particularly susceptible to degradation when exposed to air, light, and heat. However, breeding targets are set to take into account nutrient stability and retention in biofortified foods, based on typical processing, storage, and cooking practices. Nutrition research suggests that biofortified foods retain sufficient micronutrients to improve human health even after cooking.  The only potential exception is for the production of a processed products like gari, where the vitamin A cassava is chopped into minute pieces and exposed to high heat during its preparation.

Vitamin A toxicity is rare, but real. It can occur when it lasts for long periods of time, especially in areas where vitamin A supplementation and food fortification programs co-exist. However, toxicity is not a major issue when using beta-carotene as a source of vitamin A (e.g., using plant food OFSP, vitamin A maize, or vitamin A cassava). The body can regulate how much vitamin A to make from beta-carotene based on its needs. If the vitamin A status is within the normal limits, the body will reduce the expression of enzymes involved in beta-carotene cleavage to vitamin A.

References

  1. Meenakshi, J. V., Nancy, J., Manyong, V., De Groote, H., Javelosa, J., Yanggen, D., Naher, F., Garcia, J., Gonzalez, C., and Meng, E. 2010. How cost-effective is biofortification in combating micronutrient malnutrition? An ex ante assessment. World Development, 38(1), 64–75.
  1. Low, J., Arimond, M., Osman, N., Cunguara, B., Zano, F., and Tschirley, D. 2007. A food-based approach introducing orange-fleshed sweet potatoes increased vitamin A intake and serum retinol concentrations in young children in rural Mozambique. Journal of Nutrition 137: 1320–1327.
  1. Hotz, C., C. Loechl, A. de Brauw, P. Eozenou, D. Gilligan, M. Moursi, B. Munhaua, et al. 2012a. A large-scale intervention to introduce orange sweet potato in rural Mozambique increases vitamin A intakes among children and women. British Journal of Nutrition 108: 163-176.
  1. , C., C. Loechl, A. Lubowa, J. Tumwine, G. Ndeezi, A. Masawi, R. Baingana, et al. 2012b. “Introduction of B-carotene-rich orange sweet potato in rural Uganda results in increased vitamin A intakes among children and women and improved vitamin A status among children.” Journal of Nutrition 142: 1871-1880.
  1. van Jaarsveld, P. J., Faber, M., Tanumihardjo, S. A., Nestel, P., Lombard, C. J. and Spinnler Benadé, A. J.. 2005. “ß-carotene rich orange-fleshed sweet potato improves the vitamin A status of primary school children assessed with the modified-relative-dose-response test.” American Journal of Clinical Nutrition 81: 1080-1087.
  1. Gannon et al. 2014. “Biofortified orange maize is as efficacious as a vitamin A supplement in Zambian children even in the presence of high liver reserves of vitamin A: a community-based, randomized placebo-controlled”. American Journal of Clinical Nutrition 114:087379
  1. Talsma, E. 2014. “Yellow cassava: Efficacy of provitamin A rich cassava on improvement of vitamin A status in Kenyan school children.” Dissertation Summary, Wageningen University, Wageningen, Netherlands.
  1. Haas, J.D., Beard, J.L., Murray-Kolb, L.E., del Mundo, A.M., Felix, A., and Gregorio, G.B. 2005. Iron-biofortified rice improves the iron stores of non-anemic Filipino women. Journal of Nutrition 135: 2823–2830.
  1. Finkelstein et al. 2015. “A Randomized Trial of Iron-Biofortified Pearl Millet in School Children in India” The Journal of Nutrition 145: 1576-1581
  1. Haas, J.D., Beard, J.L., Murray-Kolb, L.E., del Mundo, A.M., Felix, A., and Gregorio, G.B. 2005. Iron-biofortified rice improves the iron stores of non-anemic Filipino women. Journal of Nutrition 135: 2823–2830.
  1. World Bank. 1993. World development report. Washington: World Bank.
  1. 2010. Disseminating orange-fleshed sweet potato: Findings from a HarvestPlus project in Mozambique and Uganda. Washington: HarvestPlus.
  1. The Global Nutrition Report 2014: Actions and Accountability to Accelerate the World’s Progress on Nutrition. American Journal of Clinical Nutrition 114:206078.
  1. Alderman, H., Hoddinott, J., and Kinsey, B. 2006. Long term consequences of early childhood malnutrition. Oxford Economic Papers. 58(3), 450–474.
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