Meet the Expert: Juan Bonilla

Illustration of Juan Bonilla

Juan Bonilla is a managing economist and project execution lead for the International Development Division at AIR. He studies agricultural development, nutrition, social protection, and education policy in developing countries, particularly in sub-Saharan Africa. Before joining AIR, he taught in the Economics Department at the University of Sao Paulo in Brazil. He is also a member of the editorial board of the Journal of Research on Educational Effectiveness. 

POSITION: Managing Economist

EXPERTISE: Evaluations, international development, nutrition


Q: You lead the Neglected Crops and Maternal and Infant Health study in Tanzania, which focuses specifically on the orange-fleshed sweet potato. What makes that crop unique?

Juan: In the United States, we consume sweet potatoes without much thought. But in fact, the orange-fleshed sweet potato—we call it the OFSP—is an extremely interesting crop, for a few reasons. First, it’s exceptionally rich in vitamin A, which is essential not only for good vision, but the immune system as a whole. In communities where clean water and health care are lacking, stomach infections and diarrhea can be fatal, so a strong immune system is particularly important. 

Second, the OFSP is a very resilient crop, which is particularly important because of climate change. It requires less work than many other crops; it can withstand reduced water (within limits); and it can stay underground for a long time, to be harvested at the farmer’s convenience.

Lastly, it’s very versatile to cook with: in Africa, they fry it into donuts; they turn it into chapatis; they puree it with milk and turn it into yogurt. It’s nice and sweet, so children love it.

Q: What is the intervention designed to do?

To help people discover the versatile deliciousness of the OFSP, the International Potato Center produced this recipe book, which includes OFSP pudding, sweet potato pancakes, and sweet potato juice, among others.

Juan: The goal is to improve the health of mothers and young children in the Shinyanga region of Tanzania. This particular crop was well-suited to this region because the local farmers were already producing non-orange variety of sweet potatoes. They had the necessary knowledge and equipment to cultivate these crops; they just weren’t taking advantage of the variety with the most nutritional value. In collaboration with our partners at the International Potato Center, which is part of the CGIAR consortium, we provided farmers with the OFSP vines and fertilizer, as well as agricultural, nutrition, health, and cooking trainings. 

We were not the first researchers to evaluate the OFSP for this kind of intervention. But previous studies usually look at short-term impacts, which means those studies miss the opportunity to investigate why in some communities, farmers start producing the OFSP and then abandon it. We wanted to do a long-term study that would help us understand why dis-adoption might happen, and what the outcomes would be if they did sustain production of the OFSP over time.

Q: What is the most challenging aspect of evaluating an intervention like this one?

Juan: Essentially, we’re testing the adoption of a new technology (producing a new crop), which means changing farmer behavior. And as human beings, we all struggle to change our long-standing behaviors, so there are a lot of associated challenges! Most of these farmers have produced the same crops for many, many years, and know its ins and outs. Then we come along and suggest they produce something unfamiliar, promising that it’s worthwhile because it will increase their vitamin A levels—a benefit they can’t see for themselves. 

There are also knowledge gaps, which the agricultural and cooking trainings were meant to address: explaining how to cultivate the most productive OFSP varieties, what fertilizer to use, what kinds of sweet potato foods might be sellable. But these farmers do not have insurance if, for example, the crop doesn’t grow well or sell well. For them, adopting the OFSP contains a lot of risk. We designed our intervention to mitigate the biggest challenges: We incentivized behavior change by improving knowledge about OFSP benefits and reduced the risks of cultivating a new crop by providing the initial vines and fertilizer. 

Q: What has your evaluation shown about the intervention’s effect so far? 

Juan: To evaluate the long-term impacts of the intervention, we designed a mixed-methods, longitudinal study that randomized access to inputs (OFSP and fertilizer), access to trainings, and access to both inputs and trainings in 60 villages in the Shinyanga region. In the four years since we began, we’ve seen an increase of approximately 40 percentage points in the production of OFSP relative to the control group. Not only that, but mothers and children were 75-160% more likely to consume OFSP in the different treatment groups. That data point is perhaps the most important because it is essentially an automatic increase in their vitamin A scores. 

In the last round of data collection, we found that the program already showed a reduction in the propensity of local children to be sick. We also saw a small, but statistically significant, reduction in child mortality. I don’t want to overstate that outcome, but it is the kind of effect that we would hope to see over time, as the consumption of OFSP takes gradual effect. 

Q: What is the most common misconception around maternal and infant malnutrition?

People often think that malnutrition stems only from insufficient food intake, or hunger. Food diversity is also a major problem, especially in many agricultural, rural areas like the Shinyanga region.

Juan: People often think that malnutrition stems only from insufficient food intake, or hunger. Food diversity is also a major problem, especially in many agricultural, rural areas like the Shinyanga region. Most people there eat the same thing every single day: ugali (a stiff porridge made by mixing maize or sorghum flour with boiling water), cassava, and rice, supplemented occasionally with a bit of animal protein, but very few fruits and vegetables. As a result, many children in the region aren’t necessarily underweight, but they’re very short; their physical and cognitive development are impaired by the lack of diversity in their diets.

Q: How might technology, such as artificial intelligence (AI), play a role in future agricultural development interventions?

Juan: In developing countries, a lot of information is delivered to farmers through government officials. Ideally, they advise each farm according to its specific circumstances: informing them about eligibility for studies based on the crops they grow, or suggesting fertilizer usage (types, quantities, and timing) based on upcoming forecasts. But there are very few government officials—especially compared to the number of farmers they each serve—and they have many other responsibilities besides disseminating information and advising farmers. 

AI could potentially generate excellent forecasts of what a specific farmer needs to know depending on their location. Most of these farmers have access to cell phones. Using those, the government could push out AI-generated information on optimal fertilizer use, crop varieties, and how to fight pests or diseases. 

Q: Where can we find you on a typical Saturday?

Juan: My wife and I enjoy spending as much time as we can with our two young daughters, ages 12 and 8. On a typical Saturday, you will find me taking them to music practices or sport practices. We also try to meet with friends regularly and have them over. And we like cooking. My wife and I are from Colombia, so we use a lot of those flavors—but I love cooking recipes from all over the world.

Q: What book would you recommend to anyone?

Juan: Much of my professional work has taken place in Africa, which inspired me to gain a greater understanding of the continent. Ryszard Kapuściński wrote a travel memoir called The Shadow of the Sun, which idolizes a time when many countries in the region were gaining independence. He shares a lot of good insights on the complexities and contradictions of that moment. Mia Couto, a Mozambican writer, wrote a beautiful book called Terra Sonambula (Sleepwaking Land), which deals with family relationships, identity (personal and national), colonialism, and struggles after independence. Lastly, I also recommend Things Fall Apart, a classic by Nigerian author Chinua Achebe. Many African countries gained independence in the 1960s, but this novel vividly shows how much has stayed the same in certain rural areas since then. It’s a reminder of how much work the international community still needs to do to support those communities. 

Juan Bonilla
Managing Economist