The challenge of achieving basal energy, iron and zinc provision for home consumption through family farming in the Andes: a comparison of coverage through contemporary production systems and selected agricultural interventions

Agriculture is a vital source of food for farm households in the central Andes of Peru and a main entry point for development interventions aimed at strengthening food security and reducing undernutrition. Food-based approaches to nutrition, particularly those involving enhanced on-farm production to increase yields or to incorporate micronutrient dense components such as microlivestock (e.g., guinea pigs, chickens), biofortified staples or vegetables in smallholder farming systems, are frequently considered to be robust and sustainable alternatives to enhance smallholder food security [1, 2]. Higher or more stable crop yields are expected to influence the availability dimensions of food security, while diet quality from micronutrient rich foods can directly affect food security through utilization. Importantly, enhanced on-farm production as a food-based approach to improve nutrition is considered sustainable. In contrast to non-food-based approaches where nutritional supplementation, for example, must be provided in an ongoing way by agents external to the community, food-based alternatives can be autonomously maintained by farmers.

One underexplored prerequisite for the success of food-based approaches relates to the actual capacity of the smallholder farming system to provide sufficient food or nutrients to cover basic household-level nutritional requirements. Empirical assessments of these crop–livestock systems’ energy and nutrient outputs are needed. In addition, analyses of the actual contribution of selected agricultural (food-based) interventions to household-level nutrient availability are critical to fully understand their potential impact.

Undernutrition is still prevalent in the Peruvian Andes, disproportionately affecting rural areas [3]. Stunting, or low height for age, is particularly widespread and has been the main focus of attention for governmental and civil society nutrition interventions in Peru. Stunting reflects the cumulative effects of undernutrition and poor health [4]. It is an indication of poor food and/or environmental health and results in long-term restrictions on child growth potential. Between 2000 and 2011, stunting in Peruvian children younger than 5 years of age went down from 31.6 to 19.6 %; anemia dropped from 50.4 to 30.7 % [5]. For the same period, stunting rates in Peru’s highland regions dropped from 43.5 to 30.8 %; anemia dropped from 56.2 to 39.9 %. Despite overall progress, the prevalence of anemia in children 6–36 months old has remained disproportionately high with 41.6 % at the national level and 49.6 % in rural areas in 2011 [6]. By 2013, these figures actually increased to 46.4 % nationwide and 51.7 % in rural areas.

The reduction in child malnutrition in Peru is the result of increasingly coordinated government and civil society actions, e.g., a national poverty reduction strategy prioritizing nutrition interventions [7, 8]. Nutrition programs in Peru have focused on improving food access and availability. A conditional cash transfer program (Juntos) for women and food supplementation through the “glass of milk” and “school breakfast” programs have been at the heart of governmental strategies for the last decade [8–10]. Fortification of commonly consumed products, such as wheat flour, noodles or prepackaged school breakfast meals, is also regularly applied in Peru [11, 12], but these do not target infant and young children under 3 years old—the most vulnerable group for nutritional deficiencies and their child development consequences. On the other hand, the strategy of multi-micronutrient powder or sprinkles for children 6–36 months has been applied irregularly by the Peruvian government. In addition, many initiatives have addressed food utilization practices, e.g., improved hygiene and sanitation through nutrition messaging [13].

Meanwhile, agricultural or food-based approaches in the Andes have been predominantly promoted by civil society organizations. Interventions include the promotion of small greenhouses, horticulture, microlivestock, crop diversification and to a lesser extent biofortified crops [14]. In parallel, international development programs have focused their attention on increasing farmer income through inclusive value chain initiatives [15, 16]. Food stability is probably the food security dimension that is least attended by institutional interventions. Yet, Andean practices such as field scattering, mixed crop–livestock portfolios, planting of varietal combinations are still widely used by farmers themselves to maximize stability [17–19].

Research and development organizations frequently assume that agricultural (food-based) interventions will effectively translate into significant household-level nutrition improvements. Different types of social, economic or biophysical factors can impede desired outcomes. On-farm production is taking place in the high Andes as smallholder farmers rapidly diversify their livelihoods through off-farm employment [20–23]. Male farmers are increasingly only part-time involved in agriculture, and as women stay behind, a feminization of agriculture is becoming a reality in many rural areas [24–27]. Moreover, while in some places (temporal) migration has released some of the pressure on the land’s ability to sustain food production [28], in others continued demographic pressure and landholding fragmentation reinforce migration and intensify crop and livestock production [29–31].

Particularly where smallholder farming systems may face constraints to production, it is imperative to assess actual carrying capacity and the potential of currently promoted agricultural interventions to enhance it. Carrying capacity defines the balance between land resources and human demands [32–40]. Locally, for smallholder food security, it translates into the total annual crop–livestock output being able to cover household demand for food. Sustainable intensification, it is argued, can extend the carrying capacity of the land to meet human food security needs [41–43]. In Andean agricultural systems, intensification options include the promotion of new varieties, crop biodiversity, homegardens or better practices for soil fertility, handling pests and disease, and storage of target crops, among others [44–51]. The desired outcome of such efforts is to increase the household-level food and nutrient quantity (yield) and quality (diversity, micronutrient density) under current landholding sizes.

Presently, Andean farming systems are under great strains to provide sufficient output to meet the demands of the households that (partially) depend on agriculture for food security. Among other influences, land fragmentation [52–54], interruption of communal rotation designs [55, 56], shortened fallow cycles [30, 55, 57, 58], soil degradation manifested as negative macronutrient and soil organic matter balances [43, 59–63], pest and disease intensity [64, 65], expansion of agricultural activities into higher altitudes exposed to extreme weather [66–68], and higher risk of harvest loss [69] may all compromise the basic capacity of agricultural systems and common development interventions to meet household-level nutrients demands. A deepened understanding of these intervening factors is beyond the scope of the current study. However, by taking the case of selected communities in central Peru, our research contributes with a much-needed estimate of current smallholder production system carrying capacity in terms of basic energy and micronutrient provision from agriculture. Through modeled scenarios we present a novel analysis of the capacity of specific agricultural interventions, or so-called food-based approaches, to increase the output of energy, iron and zinc from agriculture.

The purpose of our research is to examine whether agricultural output under current farming practice actually provides sufficient energy, iron and zinc output to meet household demand or input. We adopt the concept of carrying capacity to measure and compare the basic capacity of farming systems to cover household-level energy and micronutrient (iron and zinc) requirements through agriculture. Further, we explore variability among households and conditions associated with either positive or negative balances. To evaluate the contribution of food-based approaches to improve household-level balances, we analyze the effect of four agricultural intervention options. The outcome of these analyses are household-level balances: on-farm production output versus household-level demand for energy, iron and zinc.

The selected food-based interventions correspond to the strategies currently pursued by different development actors (NGOs and research for development centers): (i) enhancing potato yield, (ii) introducing biofortified potatoes, (iii) promoting guinea pigs and (iv) a combined approach. These interventions aim to eventually enhance smallholder household food and nutrition security with an emphasis on maternal child nutrition, support healthy livelihood outcomes and reduce vulnerability in the long-term [8, 70, 71]. The future implementation of such interventions would benefit from the present study. By providing an empirical assessment of the current carrying capacity of smallholder production systems and modeling specific interventions, our findings offer researchers and development practitioners information to feed into their nutrition and food security strategies.