Hidden Hunger and the Transformation of Food Systems. Группа авторов

as a valuable long-term approach to combating hidden hunger, particularly in rural populations. Evidence from HarvestPlus indicates that at the end of 2017, approximately 6.7 million farming households were reached with biofortified planting material, benefiting about 33 million people in 14 countries across Africa, Asia, and Latin America and the Caribbean. In fact, mainstreaming biofortification through public and private programs, policies, and investments has produced over 290 biofortified crop varieties [16]. Examples of successful biofortification implementation include the vitamin-A-fortified orange-fleshed sweet potato (OSP), iron-fortified rice, and zinc-fortified wheat. Furthermore, foliar treatment of crops with micronutrient cocktails (zinc, iodine, selenium, and iron) has recently been shown to increase the yield and micronutrient concentration of wheat in six countries (China, Pakistan, Mexico, India, Turkey, and South Africa) [17].

In terms of improving the micronutrient status of children, biofortification of rice with iron alone or in combination with other micronutrients may make little or no difference to the risk of developing anemia. However, iron fortification may reduce the risk of iron deficiency and increases mean hemoglobin concentrations in populations aged 2 years and above [18]. In addition, efficacy studies have demonstrated that consuming vitamin A-biofortified OSP has resulted in increased circulating beta-carotene, and has a moderate effect on vitamin A status, as measured by serum retinol across all age groups in Uganda and Mozambique [19, 20]. Future areas of investigation include identifying sensitive measures of plasma zinc concentration, as the current biomarker has limitations [16].

      Food Supply Chain

Rapid globalization and urbanization in developing countries have incited major changes to the landscape of food, especially transformations in food processing and modernized supply chains. This is observed upstream with trade liberalization and foreign direct investments by transnational food and beverage companies, including grocery and fast-food retailers. Downstream, a systemic shift in the composition and packaging of foods, as well as the ease of acquiring these foods is apparent. In the context of hidden hunger, reduction of processed and ultra-processed foods, as well as the introduction of large-scale fortification, are strategic solutions to ensuring children and adolescents meet their nutritional requirements [21].

Specifically, large-scale food fortification (LSFF) efforts have targeted the introduction of iron, vitamin A, folic acid, and iodine through various staples, including wheat, oil, rice, sugar, and salt to increase the micronutrient content of consumed foods. In some cases, fortification has been mandated and regulated by governments in response to evidence of population or subpopulation deficits in micronutrient deficiencies. In a recent review and meta-analysis, LSFF showed positive impacts on functional health outcomes in children and adolescents, including anemia and goiter in LMICs [22, 23]. Sustainable implementation of LSFF requires continual monitoring and quality control to ensure high compliance and effectiveness.

      Food Environments

      The food environment is a complex adaptive system, influenced by the wider food system, whereby various industries and actors operate interdependently and adaptively, and their interaction is often shaped through space and time. Food environments are especially dynamic and opportunistic in LMICs as a significant proportion of purchased and consumed food is acquired through traditional domestic channels, such as informal and unregistered vendors, wet markets, and street stalls [6]. Food environment dimensions include food accessibility, food availability, food promotion, food policy, food pricing, and food safety.

      Personal and external food environment interventions target the built and natural physical environments, legal and political environments, socioeconomic, and cultural environments. Food systems offer many entry points to improve children’s nutrition, and these environments are the points with which children and their families directly interact, including in the home, school, workplace, and consumer and retail spheres.

      Consumer and retail food environments inadvertently shape food access, availability, affordability, and media promotion. Through laws and policy, governments should ensure multilateral and bilateral trade and investment agreements are aligned with encouraging healthy, micronutrient-rich, and safe food environments. At the same time, evidence-based subsidies and food taxation have become strategies to minimize food deserts and swamps. Additionally, improving public health nutrition literacy through national and local social and behavior change communication and food-based dietary guidelines all serve to increase awareness and influence consumer behavior [6].

At the household level, decision making and purchasing power relating to food, sociocultural beliefs, as well as intra-household food allocation, are key factors in addressing hidden hunger. Adolescents, but especially children, may not have full autonomy and choice over what is made available to them and what they consume. This includes what is available in their homes, what their parents or providers purchase, and what the household can afford. In a LMIC context, girls are at a greater risk for micronutrient deficiencies due to cultural and social norms that prevent equitable food distribution [5]. In parallel, globally, school-aged girls more often than school-aged boys do not enroll for or consistently attend school [24]. Therefore, interventions and social safety-net programs delivered through the school system, such as school feeding programs or increased availability in school cafeterias of micronutrient-rich foods like fresh fruits and vegetables, which offer an opportunity to improve the micronutrient status, are not advantageous to out-of-school children.

In addition, with nutrition transition on the rise globally, school food environments have become frequent sites for unhealthy, micronutrient-poor food access, availability, and promotion. In a review and meta-analysis of unhealthy food and beverage marketing interventions to children, there was a statistically significant increase in dietary intake (mean difference 30.4 kcal, 95% confidence interval 2.9–57.9) during or shortly after exposure to advertisements [25]. This finding led to the development of 12 recommendations adopted by the World Health Organization and endorsed by the World Health Assembly aimed at reducing the impact of marketing foods high in saturated fats, transfatty acids, free sugars, or salt to children. Examples of environmental interventions specific to school-aged children and adolescents include policies that incentivize school vendors (tuck shops, canteens) to offer healthier food options, and the removal of advertisements and media which promote unhealthy eating.

      Behavioral Change

While efforts to improve accessibility and availability of healthy food options are essential to improve nutrition, behavior change in children and adolescents and their consumption practices are paramount to effectively address hidden hunger. This demographic should be equipped with knowledge and awareness of healthy and unhealthy food options, to guide their preferences and life choices, not only in their childhood and adolescence, but also into their adulthood. Children who consume fruits and vegetables in their childhood are more likely to maintain these healthy habits into adulthood, and to implement these habits with their children in their own households [26]. However, the low consumption of fruits and vegetables replaced by high consumption of micronutrient-deficient