Upping the Orange

Sherry Tanumihardjo is a CALS professor of nutritional sciences and director of the Undergraduate Certificate in Global Health, a popular new program that draws participants from majors all across campus. She has almost three decades of experience working with vitamin A, and her research team has conducted studies in the United States, Indonesia, South Africa, Ghana, Burkina Faso and Zambia. Tanumihardjo has acted as a consultant to many studies throughout the world to assist with study design and appropriate standardization. She is a strong advocate for the promotion of nutritionally enhanced staple foods, vegetables and fruits to enhance overall health and well-being.

Describe your work with orange vegetables.
I have worked for a number of years on carrots of many colors as well as on orange-flesh sweet potato and, more recently, orange maize. Basically we are trying to improve the vitamin A status of individuals by having them consume more orange fruits and vegetables in general.

Can you give us an idea of how you go about doing that?
For many years I have worked with carrot breeder Phil Simon in the Department of Horticulture. He was breeding carrots for more orange color. We did a series of studies in both an animal model and in humans, trying to look at the uptake and distribution of the carotenoids that give the vegetables their orange color—and the vitamin A that is made from the carotenoids. Then we moved on to orange vegetables in humans in Africa. I have worked with orange-flesh sweet potato in South Africa and with orange maize in Zambia.

Can you describe the connection between the color and the nutritional value?
There are three well-known precursors of vitamin A that are called pro-vitamin A carotenoids. Those are beta-cryptoxanthin, alpha-carotene and beta-carotene. Many of you may have heard of beta-carotene because it is one of the compounds found in many over-the-counter supplements. But those are also the compounds that give carrots and orange maize their bright orange color.

What happens if there is not enough vitamin A in the diet?
The most drastic thing that can happen is death. So we go around trying to get people to improve their vitamin A intake not only to prevent death—there are many steps before that happens, and one of them is blindness. Vitamin A is extremely important in vision and it also helps us ward off disease, so it’s a very important vitamin.

How did you get started in Africa?
It actually started very slowly. I used to be a consultant and I would fly back and forth to different countries to help them look at study design. The sweet potato study was funded by the International Potato Center. I helped them design the study, they did the school implementation—a feeding study—and then I helped them get the work published. My work with orange maize started in 2004 in collaboration with HarvestPlus, a project managed by the International Food Policy Research Institute. We started working with animal models and then progressed to full-fledged feeding trials, the latest of which we finished in 2012.

What were some of the challenges in your work in Africa?
The challenge is that feeding trials, if they’re going to show what we call efficacy, have to be highly controlled. So that means you have to keep the children for long periods of time and feed them all of the foods—and the foods need to be the same across the group except your test food. So in South Africa we fed orange-flesh sweet potato to half the children and white-flesh sweet potato to the other half. And then when we moved on to orange maize we did two studies. One study was similar to the sweet potato study where we fed white maize and orange maize. And then we did a second study where we had three groups, which got a little more complicated. We had white maize, orange maize and then white maize with a vitamin A supplement.

Another challenge is that all of the human work that I do involves blood—so we have to take blood from these children. Vitamin A in the human body is stored in the liver, and we use indirect markers of liver reserves of vitamin A that you can pick up from the blood.

Looking down the road what kind of goals do you have for your research?
We would like for people to have optimal health by having a diet that has not only all the nutrients you need but also some of the potential compounds that gear us toward optimal health. So it’s not just about fighting blindness anymore, but to see if we can get people into a new nutritional state where they are actually able to ward off diseases such as cancer.

What kind of progress have you made?
We have had significant progress with sweet potato. Most people in Africa used to eat white sweet potato, not the orange sweet potato we eat here in the United States. Many countries in Africa have now adapted the vines to be orange-flesh sweet potatoes. We think that’s a success story. Regarding orange maize, there are three lines of orange maize that have been released by the Zambian government. Currently orange maize is available to consumers. Right now it’s at a premium price, but hopefully with time the price will come down to the level of white maize.

How did you get interested in this line of work?
It chose me. It wasn’t something that I was looking for, but I was working with vitamin A and if you’re working with vitamin A and status assessment, it’s going to draw you to the countries that may have a history of vitamin A deficiency.

Can you talk a little more about the international nutritional programming you’ve been involved in?
Most of the work that I’ve done is to support biochemical labs. We have not done a lot of nutrition education on the ground, although that is a goal of mine, especially in Zambia. We have discovered that Zambians actually have really good sources of vitamin A in their daily diets, so we want to help them continue to eat the fruits and vegetables that are good sources of those phytonutrients and vitamins and minerals.

The other thing that I work on is isotope methods, which sounds a little scary!

What are isotope methods and what do they do?
We work with a compound called 13C. Typical carbon in the human body is 12C and radioactive carbon is 14C. We are working with the form of carbon that constitutes 1 percent of the human body. It’s perfectly safe to use, but it also has allowed me to work with the International Atomic Energy Agency. That’s the same agency that oversees radioactive bombs in different countries, so it’s kind of interesting that they have something called Atoms for Peace. And they actually received the Nobel Peace Prize one year based on the safe use of isotopes in nutrition.

I have worked in several countries trying to help them understand isotope methods and to apply isotope methods at the population level to inform public health policy. It’s a very technical method, but it can answer questions of public health significance.

So it’s a research tool. And what kinds of questions does it answer?
It is the most sensitive marker of liver reserves of vitamin A. Basically what we do is we give a dose of vitamin A that has a slightly higher amount of 13C than what’s found naturally in the environment, and then we can follow the uptake and the clearance of that 13C in the human body. And from that we can calculate total body stores of vitamin A—how much is in the whole body.

To conclude here, there’s an interesting story about your office and a more recent career development of yours—serving as director of the Undergraduate Certificate in Global Health, a program you helped develop and launch in 2011.
Yes. The Nutritional Sciences Building was originally a children’s hospital, and this particular office that I sit in sat idle for many, many years, used only for small committee meetings and things like that. When we received funding for the Undergraduate Certificate in Global Health, I looked in this office again and realized that it now fits my purpose. Originally it was the viewing room for children who had died from a variety of diseases, and the parents would sit in this room and mourn their lost child. I decided that this room fit my new mantra at the university, which is to empower undergrads, to mobilize them, to try to change the world. And while I’m sure we won’t have 100 percent participation, we’ve already had about 1,000 students go through the program.

Field Notes: South Africa

In the fertile, rolling hills of the Eastern Cape province of South Africa, it’s hard to imagine a food shortage. But hunger is a serious threat there, espe- cially for children. The area also has high levels of poverty and HIV infection.

Researchers at the CALS-based Center for Integrated Agricultural Systems (CIAS) are teaming with local groups to try to improve those condi- tions. Together they have formed the Livelihood, Agroecology, Nutrition and Development project— LAND for short—to address the region’s complex, interrelated problems.

“Using a participatory approach, we have built strong ties with local villagers and their co-op, the Ncedisizwe Co-op, which means ‘helping the nation,’” says CIAS director Michael Bell, a professor of community and environmental sociology.  The Ncedisizwe Co-op encompasses 800 small- holder farmers in 26 villages.

Other local partners include the Indwe Trust, an NGO focusing on sustainable development, and Kidlinks World, a Madison-based charity dedicated to AIDS orphans and other vulnerable children.

The group’s goals are to provide sustainable livelihoods for smallholder farmers and their com- munities; to integrate health and nutrition with sus- tainable agricultural practices; to enhance ecosystem services such as crane habitat, erosion control and carbon sequestration; and to strengthen communi- ties through participatory decision-making.

Better use of grasslands will be key in those efforts, researchers say. “The people of this region are blessed with a wealth of grassland resources, but these resources are literally being eroded before their very eyes,” says agronomy professor Randy Jackson, who accompanied the LAND team on a recent visit. “Much of this is attributable to a governance system that treats most rangelands as unregulated commons, resulting in continuous grazing that promotes unde- sirable plants and exposure of bare ground.”

Rotational grazing, the group notes—which actually originated in Africa—will potentially double the level of animal production while also building soil quality, reducing erosion and promoting wildlife habitat. LAND has conducted workshops with farmers on rota- tional grazing and helped develop a supply chain connecting local grass-based meat to national and international markets.

Other activities have included helping form a women’s cooperative for vegetable production, working with community members on improving water supplies, and helping establish perennial home gardens to increase the quality and variety of local diets.

The LAND project has matured to the point where it can serve as the basis of a new global health certificate field course, “The Agroecology of Health,” that debuted this past winter. Bell and doctoral student Valerie Stull brought 10 undergraduate and two graduate students to the Eastern Cape for a 15-day visit that encompassed learning about agroecology and hydrology systems and working with community members to establish a one-acre vegetable garden at a school in the village of Kumanzimdaka.

The students planted herbs, tomatoes, onions, peppers, cabbage and radishes and plotted locations for future fruit trees.

“The experience left me feeling a tremendous amount of respect for the people in the community who continue to live off and use the land,” says Alexa Statz, a junior in life sciences communication. “I have high hopes that the garden we built together will be something that can stay with them for generations to come.”

Bell plans to continue having undergraduates participate. Learning about themselves and their place in the world, questioning and thinking critically were all objec- tives of the trip. “But the biggest objective was to provide students with the chance to discover what it means to lead a life of consequence,” Bell says. “Now that’s a pretty grand goal—and I think it happened in South Africa. It clicked.”

Expanding the Global Classroom

A LITTLE MORE than two years ago I started cold-calling CALS faculty and instructional staff requesting no more than 25 minutes of their time. The first thing I asked the dozens of respondents who agreed to my conversational survey was: “What do you already do to introduce your students to the international aspects of your field?” Then I asked: “What would you do?” And then: “What would you need to do it?”

Their answers were as varied as the sometimes spontaneous, often revisited and always generous conversations I enjoyed over the next few months. Some wanted technical support to connect their classrooms with equivalent courses in other countries. Many were eager to host their international colleagues as guest lecturers. Some envisioned podcasts and websites designed to share relevant teaching resources. Still others conjured up entirely new majors, or a renewed system for rewarding teaching engagement across campus more generally. All of them were eager to tackle the challenge.

In the end, three common needs stood out: more opportunities to collaborate with partners abroad; time to put new teaching projects together; and graduate student assistance to pull it off.

The CALS International Programs Office was prepared to meet those needs with a small awards program under the auspices of the campus-wide Madison Initiative for Undergraduates. International Programs director John Ferrick and undergraduate program development director Laura Van Toll conceived of the program to support science faculty interested in further introducing their students to the international aspects of their fields; I was brought on to help carry it out. We asked for “global learning outcomes” in the awards application so that we could learn the skills and perspectives instructors wanted their students to gain. And we gathered a group of faculty to evaluate and lend insight into the feasibility of their colleagues’ projects.