At Colorado State University, an unlikely partnership between a breast cancer researcher and a bean breeder yields exciting results.
By Dario Bard
Chance conversations are the fountainhead of good science. So states Dr. Henry Thompson, a breast cancer researcher at Colorado State University. It was just such a conversation, he explains, that led him to look into the cancer-fighting properties of dry beans. The exchange took place on the campus of Colorado State University, in the Department of Horticulture and Landscape Architecture to be exact, and Dr. Thompson’s interlocutor was Mark Brick, the university’s sole bean breeder. On Brick’s mind at the time was a request for proposals issued by the U.S. Dry Bean Council about six months earlier.
“Around 2004, the Council teamed up with industry members, particularly Archer Daniels Midland and Bush Brothers, and lobbied for federal funding to work on the health beneficial properties of beans,” says Brick. “So I’m walking down the sidewalk and here comes Henry.”
“So I do my howdy do,” says Dr. Thompson, “and Mark stops me and says, ̒ Hey, Henry, by the way, I work on beans and I think beans are really good for you. Would you be willing to take a look at whether or not they have anti-cancer activity?’ And I say, ‘Sure!’ Because that is exactly the kind of conversation I was hoping to have when I moved my lab to Horticulture and Landscape Architecture.”
On that suggestion, Dr. Thompson and Brick submitted a proposal to the U.S. Dry Bean Council and received funding to pursue their research.
“The first time we ran the experiment,” recalls Brick, “we used chickpeas, beans and cowpeas. When the results came in, Henry said, ‘This is the most astounding thing I’ve ever seen. Look here … it reduces the incidence of cancer by almost 50%!’ Beans turned out to be better than chickpeas and cowpeas. We didn’t believe the data, so we designed another experiment to see if we could replicate the results. The results were the same. I suggested we do it a third time, this time with beans from the following crop year. So we did, with Bush Brothers providing the canned product, and we got the exact same results. So we knew we were onto something.”
The results of the second and third experiments were published in Crop Science (vol. 49, January-February 2009) and embarked Dr. Thompson and Brick on a series of research projects that found that including dry beans, particularly white kidney beans, in a diet inhibited the spread of cancer by as much as 70%. Their line of research eventually caught the attention of the National Cancer Institute (NCI), which awarded Dr. Thompson and Brick a five-year grant.
Intrigued by this fortuitous collaboration between a cancer researcher and a plant breeder, IFT interviewed both Dr. Thompson and Brick about their partnership.
IFT: Dr. Thompson, your cancer research lab is actually located within Colorado State University’s Horticulture and Architecture Department, right? That is a bit unusual, isn’t it?
Dr. Thompson: The story behind that is that 15 years ago I was very much focused on fruits and vegetables, as everybody who is interested in health tends to be because of their strong anti-oxidants. I was doing clinical studies on women with breast cancer and we were assessing markers of oxidative damage in blood and urine. What we found is more improvement in these markers when women switched to our low-fruit-and-vegetable control group than when we had them go from 3 to 12 servings per day. That’s when I decided I had to understand more about the decision-making process in agriculture and moved my lab from a cancer center to CSU’s Department of Horticulture and Landscape Architecture.
IFT: Was that move well received within the department?
Brick: I think the merging of these two disciplines made all of us better, but, you know, in institutions there is always a fear about an outsider coming in that doesn’t belong, so to speak. Some people felt it was a mistake, but the dean at the time, Dr. Marc Johnson, got to know Henry when Henry had his own research lab in Denver, looking at the effects of exercise and nutrition on breast cancer survivors, so when he arrived at the department, food became more important. And quite honestly, if there is one thing we can contribute to the discussion about the health beneficial aspects of food, it is that there is a great deal diversity within every food. For example, we opened up the can of worms that not all beans are the same. There is a lot of genetic diversity and we can exploit it. That’s the big thing that came out of our partnership.
Dr. Thompson: That’s right. When we looked at the data, Mark said, “Henry, you look at the data and you got to say that all beans are good.” And I said, “Mark, I agree with you, but you must also agree that maybe the evidence indicates that some beans are better than others.” Everything sure suggests from the nutritional point of view that all beans are good, but there’s a story about white kidney beans; they are the best at inhibiting the development of cancer, particularly breast cancer. Why is that? I suspect it is not the nutrients but that it relates to other chemicals that are present in the bean that are preventing activity. So that is the work we are pursuing. We are in the second year of a five-year grant we received from the National Cancer Institute to better understand the cancer inhibiting activity of common beans, specifically white kidney beans.
IFT: Mark, how did your expertise as a bean breeder contribute to Henry’s research?
Brick: When Henry and I started talking, he asked me a lot of questions about beans and where they came from. I started telling Henry about the origins of beans and how they were domesticated in two different regions, one in South America and the other in Middle America, in Mexico, and how these two groups of beans are quite distinct in their genetic background because they were domesticated independently. I showed him seeds and he came out to the field plots and was astonished at how things were. Like most non-agronomists, he thought corn was corn and beans were beans. Whether you get them from the grocery store or the fields, it’s all the same, and of course it is not. That really excited Henry, and when we prepared that U.S. Dry Bean Council proposal, we designed it with genetic diversity in mind. We had two Andean lines and two Middle American lines from Mexico’s highlands and another two Middle American lines from Mexico’s low, tropical regions. That way we had three very diverse groups of two entries each. Each group had a white and a colored bean. When we ran the experiment, the best bean turned out to be the white Andean bean.
Also, my contact with Bush Brothers helped in getting the right kinds of beans. So the genetic component and the industry contact is what I brought to the table. Of course, clearly, if it weren’t for Henry, I couldn’t have done this. And I guess you could argue that if I hadn’t been involved, it would have been done quite differently. He would have probably picked the beans off a grocery store shelf and there are a lot of problems with that approach.
So I think we made a good team. We were synergistic in our thoughts and we tested each other. We are still very open and honest with one another. We can criticize the other without problems. That also made for a better study.
IFT: Tell me more about the work you are doing under the NCI grant.
Dr. Thompson: The NCI is interested in isolating the chemical in white kidney beans that are responsible for the cancer-inhibiting activity so that you can then make a pill. But I have a different philosophy. I don’t want to take beans and break them down into their ingredients. My goal is to understand beans as a food. I want to identify those special traits, like there seem to be in white kidney beans, and work with my plant breeder friends to select for those traits across all bean varieties. The idea is to breed not only for better agronomic traits, but also for nutritional traits.
My long-term goal is to promote bean consumption because it is good food, and food has very powerful effects on our health. I think we have lost sight of the power of food. If you look at the American plate, pulse crops have essentially disappeared. We need to change that. My whole point is to get people to focus on the importance of food and to get agriculture producing the best foods that can possibly be put on the table.
I like to say that beans are an ancient solution to 21st century problems. In the biomedical sciences, we don’t recognize that pharmacology was originally about what you eat. Pulse crops have disappeared from the American palate, and so we are missing a piece that pharmacology itself has abandoned. If you look at the staple food crops, there’s rice, wheat, corn, potato and pulses. Pulses have always been paired with one of the other four. That is, independent population centers 10,000 years ago or more paired them. Why have we stopped? Now things have flipped; we think of animal protein and soy products as substitutes for pulse crops. There is nothing wrong with soy and animal protein, but I don’t believe they are a substitute for pulses. We better get consumers back to eating pulses every day.
The consumer should appreciate the power of food and the dietary choices they make. Beans are the authentic, low-fat, high-fiber, minimally processed food that should be on our plates in abundant amounts every day. Beans are environmentally sustainable. They are affordable and accessible. They are loved by the populations of the world. Everyone should be taking advantage of that. We should all be eating a cup and a half of pulses every day. And it’s not that hard to do. There’s a lot of lost pulse know-how. You can have beans and an egg rolled up in a wheat tortilla for breakfast and that is a remarkably healthy meal. It takes three to four minutes to prepare and it provides a woman fighting cancer with a good, solid breakfast that weighs in at less than 300 calories. And that can be done with every meal and with snacks, too. I have a granddaughter and her favorite finger food is kidney beans, a wonderful snack. For dessert, I’ve had to-die-for cheesecake and mud pie made from beans and chocolate; you are not even aware the beans are there in the flavor profile, and that’s half a cup right there.
Brick: It is important to note, also, that beans and cereals complement each other. Between the two, you have all the amino acids you need, so it’s not about just eating beans. It’s about including beans in a balanced diet.
Dr. Thompson: Right. The thing with beans is that they are packed with fiber. They are the best source of fiber, far better than other grains. Of course, it’s not an either/or thing. You ought to combine them. The thing with pulse crops is they don’t have much flavor, so you can add them to flavorful dishes and you won’t even notice the pulse crop is there.
IFT: One way the industry is hoping to increase pulse consumption is by adding pulse ingredients into processed foods. What do you think of that approach?
Dr. Thompson: I’m not a big ingredients fan. I understand why the industry is going down that road and how it helps create a new market for pulse producers, but the ingredients approach runs counter to the whole food concept I am promoting.
Look, there are four interrelated disease that account for at least 60% of deaths globally: heart disease, type-2 diabetes, obesity and cancer. A healthy diet goes a long way in fighting all four of these. So I say let’s focus on food. You don’t know what you lose when you break whole foods down into their ingredients. Besides, consumers want to get away from processed foods.
Brick: Henry and I don’t necessarily agree on this one. As I see it, there is a diversity of people and incomes in the world. This is a world problem, not a U.S. problem. In developed countries, most of what people eat is processed. You have a captive market there. You could put good things into the processed foods they eat and they would never notice. I think that is too great an opportunity to pass up.
Like Henry, my preference would be to have people eat whole foods, but I think either way, pulses have something to contribute.
IFT: What has been the reaction of the bean breeding community to your call to breed beans for nutritional traits?
Dr. Thompson: The response has been extremely receptive. They are a warm and welcoming community of scientists, and I think they are hungry for some new approaches and new ideas.
Brick: There has been similar research done in the past. At Michigan State University, they looked at bean consumption and colon cancer, and at Washington State University they looked at the nutritional properties of pulses. But those efforts didn’t get a lot of traction from the bean science community. The scientific community just didn’t see it as something that was going to enhance feeding the world calorie-wise, and agronomists understand feeding the world to mean providing calories. The error there, though, is that pulses provide calories and nutrition: protein and macro- and micro-nutrients, fiber and other things that are beneficial to health but that don’t necessarily contribute to calories.
So the work we are doing is raising awareness, no doubt. If you talk to the American Pulse Association, Bush Brothers, ADM, they are interested in health. So I think we are on a roll and have definitely come a long way.
IFT: Are you working on something new at the moment?
Brick: We just completed a study on bean fiber. Like we said earlier, beans are packed with fiber. The study looked at 300 varieties of Middle American beans for dietary fiber. We saw a range from a low of about 21 to a high of almost 30. That translates to genetic diversity. The next step is can we improve it? Can we reduce the insoluble and enhance the soluble?
Right now, we are in the process of writing the manuscript. The big takeaway is that we now know that we can design dietary fiber into beans to provide the best health beneficial aspect to humans.
IFT: The last question is for Mark. One thing that has come across in this interview is Dr. Thompson’s enthusiasm for dry beans. Do you think it is fair to say you turned him into a dry bean evangelist?
Brick: No doubt about it. I’ll take credit for that. That was my doing and I’m proud of it. I think it is the biggest accomplishment of my career.