Little Beans, Big Opportunities

In the U.S., 75% of health care costs are attributable to preventable chronic diseases, mostly linked to excessive calorie intake and insufficient exercise. This dietary imbalance devours lives as well as money. For centuries, every generation in the U.S. has lived longer than the previous generation. That trend reversed a decade ago; children born within the last 10 years are expected to live shorter lives than their parents, largely because of their skyrocketing rates of preventable chronic diseases.

Tragically, as incomes rise in developing countries, people there flock to the same eating patterns that are now killing Americans. China and India each have about 300 million people in their middle classes, and "[people] are switching over from a plant protein–based diet to an animal protein–based diet," Ramaswamy said. More energy and more water are required to produce meat calories than to produce plant calories, and with current trends in environmental degradation, climate change, and land and water constraints, this dietary switch could not come at a worse time.

Pulses have numerous health benefits. (Image courtesy of Sonny Ramaswamy)
"Pulses have just the perfect sweet spot of characteristics" to solve these challenges, Ramaswamy said. Beans yield abundant harvests of protein, vitamins, complex carbohydrates, and fiber for a minimal investment of water, fertilizer, and effort. Unfortunately, they are often neglected in favor of more lucrative crops.

Beetles in the beans

For decades, crop breeding and nutritional research has focused on corn, wheat, rice, and a few other plant species, largely ignoring pulses. The science that has been done on pulses has, however, generated promising results for improving crops and yields. Ramaswamy pointed to the grass pea Lathyrus sativus, a very hardy pulse that farmers in Asia and Africa rely on to produce harvests even when other crops fail. L. sativus produces a neurotoxin that causes lathyrism, a neurological condition with symptoms similar to multiple sclerosis. Scientists recently developed a strain of the plant that lacks the neurotoxin; widespread adoption of it could substantially reduce both starvation and lathyrism.

Advances in gene editing technology, as well as a new focus on traditional crop breeding, could soon yield additional improvements in beans. "We believe that there are really excellent possibilities for us to enhance the already fantastic food item that we've got," Ramaswamy said.

Insect-resistant pulses could yield large benefits for developing countries.
Insect-resistant pulses could also become invaluable, especially in developing countries. Ramaswamy described an experience he had as an entomologist studying pulse pests in Africa. In a food market, he and his colleagues noticed a sack of beans crawling with insects. The shopkeeper solved the problem by pouring a cocktail of hazardous pesticides on the bag. "About two minutes later, in comes this little bitty girl about four or five years old ... and she was going to take [the beans] home and be exposed to all those pesticides," he said.

Several types of improvements could overcome pulse crops' current limitations. (Image courtesy of Sonny Ramaswamy)
Improved pulse crops, and increased pulse consumption, could also reduce food waste, which is a problem in rich and poor nations. In developing countries, a third to half of the food farmers try to grow is devoured by pests. Pesticides are either unaffordable or poorly regulated, leading to incidents like the one in Ramaswamy's story. Insect-resistant pulse varieties could provide a much-needed increase in the available protein in those areas.

Farmers in developed countries have easier access to safer insecticides; ironically, this availability has led to food surpluses, overeating, and nearly as much food waste. Instead of losing a third of the crop to insects, these countries now lose a third of it to garbage disposals. Improved diets, including consumption of more plant-based protein, would reduce the excess food demand in these countries and the energy used for growing food.

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Collaboration among governments, the food industry, academia, and the public will be needed to solve the manifold problems in global food supply. Academic researchers are already studying these issues. Ramaswamy pointed to a project at Colorado State University, which received a $2 million grant from NIFA to study how bean consumption affects dietary biomarkers in humans.

New consumer technologies, such as wearable sensors and computerized dietary analyses, are also converging on a trend Ramaswamy calls "precision food." "All of these things are coming together, including food analysis, lifestyle, and behavior, [and] I believe we're tantalizingly close to being able to address that nutritional security issue," Ramaswamy said, referring to the twin global threats of starvation and obesity. The USDA has taken an active role in this effort, releasing a smartphone application called SuperTracker, which provides personalized diet and exercise recommendations based on food intake and activity levels.

Audience questions and comments after the talk included a proposal to use heat to clear infestations in stored pulses and a call to shift priorities in government programs that are currently geared toward other crops. One audience member also pointed out that the USDA could promote pulse consumption by allowing pulses to count as a meat substitute in its national school lunch program.

Pregnant and nursing women need to increase protein intake and consume higher amounts of several vitamins and minerals. Infants then need substantially higher dietary levels than adults of iron, zinc, and other nutrients; but because their stomachs are small and inefficient, babies must consume large amounts of food just to meet their daily needs. In many areas, the standard foods for infants are cereal-based porridges, which have low nutrient density and lack many essential vitamins and minerals. As a result, millions of children start their lives malnourished.

Diversifying the diets of pregnant women and babies can help. Blending cereals with higher-protein foods such as pulses and mixing mineral supplements into the foods offsets some of the nutrient deficits. However, even these blended diets do not provide all of the micronutrients infants need.

Infants need more nutrients than adults. (Image courtesy of Seth Adu-Afarwuah)

Adu-Afarwuah's team designed an intervention to fortify the diets of new mothers in three countries plagued by childhood undernutrition, Malawi, Ghana, and Burkina Faso. In four randomized controlled trials, the researchers gave expecting mothers lipid-based nutrient supplements made from vegetable oil, powdered milk, peanuts, sugar, and micronutrients. Infants in the experimental groups were consistently heavier and longer and developed larger head circumferences than those in the control group. Pregnant women who had the highest risks for raising malnourished babies benefited most.

Adu-Afarwuah cautioned that supplements will not automatically solve the infant malnutrition problem. Distributing the supplements in poor countries is hard, the mothers who would benefit most are least able to afford them, and widespread infectious diseases may offset many of the advantages of food fortification in the poorest areas. "We want to think about a menu of interventions, not just one intervention that is capable of solving one problem," he said.

Good for your heart

John L. Sievenpiper of the University of Toronto talked about the growing number of people who suffer from the consequences of overnutrition: obesity, type 2 diabetes, and cardiovascular disease. Public health officials project that over the next 20 years, global rates of type 2 diabetes will increase by 55%. "Diabetes is really ... poised to bankrupt the health services with these sorts of increases," Sievenpiper said.

Overnutrition is a public health disaster. (Image courtesy of John L. Sievenpiper)

Because type 2 diabetes and cardiovascular disease tend to occur together, researchers have tried to develop drugs targeting both. Those efforts have yielded a success: acarbose, a compound that simultaneously lowers blood sugar and reduces the incidence of cardiovascular events.

Acarbose works by slowing the absorption of carbohydrates in the intestine. However, some foods—particularly pulses—have the same effect. "We tend to view pulses as a nutritional model of acarbose," Sievenpiper said. Several studies on the acute effects of pulses have shown that pulse-based meals decrease starch digestion and lower postprandial blood sugar compared to meals with higher grain contents.

Current dietary guidelines tend to include pulses in the general category of legumes, mainly as alternatives to meat. The developers of these guidelines, including the USDA and the researchers it consults, have not explored whether pulses can promote long-term improvements in diabetes and cardiovascular disease. "Clinicians and dieticians that are on these committees ... weren't asking the question," Sievenpiper said. He added that when clinicians hear the term "pulse," they generally think of vascular rather than dietary pulses.

To answer the question, Sievenpiper's team performed meta-analyses of the scientific literature on dietary pulses. In 38 clinical trials, meals with pulses resulted in about 50% lower postprandial blood sugar spikes compared to meals with bread or potatoes, an effect similar to that of acarbose. An analysis of ten other trials showed that pulse-based meals produced greater feelings of satiety than control meals without pulses, possibly reducing overall food consumption. Similar analyses revealed that pulse consumption helps control blood lipids, reduce blood pressure, lower body weight, and reduce the risk of cardiovascular events.

While these data supporting increased pulse consumption are strong, Sievenpiper conceded that the field needs larger and longer trials of pulse-rich diets. Ideally, those trials would include direct comparisons to drug interventions such as acarbose.

Bug food

Mark J. Manary of Washington University School of Medicine in St. Louis shifted the focus to the gut, an organ that has recently gained new respect for the diverse bacterial ecosystem it hosts. Though microbiologists have long known that this microbiome existed, the recent availability of high-throughput sequencing techniques has begun to reveal just how important microbes are to intestinal health.

The microbes in the gut extract nutrients from food, help form a barrier between the inside and the outside of the body, detoxify poisons, and promote the development of a healthy gut lining and immune system. "The gut cells don't grow unless they have these microbes around them," Manary said. "We need these microbes."

The gut lining is a critical barrier. (Image courtesy of Mark J. Manary)

A dysbiotic bacterial ecosystem leads to enteropathy, degrading the lining of the intestine and reducing nutrient absorption substantially. The condition is uncommon in healthy people with good sanitation, but in some areas, such as sub-Saharan Africa, it is endemic. Enteropathy in children is a major factor causing stunting, a debilitating growth defect found in 40% of 3-year-olds in rural Africa. Numerous organizations have tried to reduce stunting through interventions to improve diet and reduce infectious disease rates. Manary argued that neither type of effort will work if the gut microbiome does not heal, and said that current interventions appear to fail on that score.

Pulses could help. The small intestine absorbs easily accessible nutrients, such as carbohydrates from grains, so feeding the microbes in the large intestine requires eating resistant starches, which are found in pulses. In theory, eating more beans could help feed "good" gut flora, restoring healthy gut microbiomes in undernourished children.

Manary and his colleagues are now testing that idea. In a pair of randomized controlled trials, the researchers are providing poor mothers in sub-Saharan Africa with powders of cooked legumes to add to children's daily meals of corn porridge. The studies, expected to conclude in 2016, will test markers of gut health, including microbial markers, as well as overall growth rates. "What we expect is to be able to have something to say about complementary foods with legume bases in them, and we're really looking for a big swing there," Manary said. If the data support this approach, the bean powders would be easy to distribute on a large scale.

Like most simple stories, this tale of steady progress conceals more complex realities. Cereal crops have certainly become more available and cheaper, but the real prices of milk, meat, fish, and most vegetables have gone up. Developing a more balanced agricultural system will require grappling with diverse problems in different countries.

Food choices result from a complex set of interactions. (Image courtesy of John McDermott)

Diets are inevitably shaped by a combination of needs, wants, economic realities, environmental constraints, and crucially, choices made by farmers. "We can't deliver a nutritious food to somebody if nobody grows it," McDermott said.

Most changes in the food system are the result of private-sector decisions, and McDermott separates this sector into three areas: agricultural businesses, food businesses, and connecting businesses. Government subsidies and economies of scale affect the agricultural business. If subsidies were coordinated with improved, higher-yield pulse crops and production systems, the supply of pulses would increase and prices would fall. Food businesses such as grocery stores can better market pulse products, but only if the supply is reliable. Finally, intermediaries such as food distribution and logistics companies can ensure that the crops reach consumers with minimal losses to pests and rot.

Pulses on MyPlate

Joanne Slavin of the University of Minnesota focused on the U.S. Department of Agriculture's influential Dietary Guidelines for Americans, which are updated every 5 years through a lengthy public process. To ground the guidelines in science, the USDA observes a hierarchy of different types of evidence that can support a dietary recommendation. Expert opinion is the least convincing form of evidence the department will consider, and randomized controlled clinical trials are the most convincing. Other types of data fall in between.

The food industry is well aware of the power of the USDA guidelines and the need for evidence to make changes in them. "You have to remember that your competition, like dairy, have done a ton more studies than pulses have, so you're really way behind," Slavin said. More research on beans, particularly high-credibility projects such as randomized trials, could help in persuading the USDA to recommend more pulses.

Slavin pointed to the example of whole grains, a category of foods that had not been discussed much until recently. During the 2005 update of the dietary guidelines, the USDA recommended that half of people's daily grain consumption should be in the form of whole grains. Grain giant General Mills funded much of the research backing that change.

The USDA Dietary Guidelines Advisory Committee develops U.S. dietary guidelines. (Image courtesy of Joanne Slavin)

The 2010 guidelines and the associated "MyPlate" graphic recommended that fruits and vegetables account for half of daily calorie intake and highlighted beans and peas as good sources of protein, iron, and zinc. The 2010 guidelines also allowed pulses to count as either a vegetable or a protein for dietary planning. Slavin argued that although these recommendations are a good start, pulse promoters could do better with a stronger research portfolio.

Small beans

Allan Hruska of the UN Food and Agriculture Organization talked about the United Nations' sustainable development goals, which focus on ending poverty and hunger globally. Agriculture is at the crux of both issues. "Ninety percent of the extreme poor in the world live in rural areas and are directly related to agriculture," Hruska said. Many of those people also rely heavily on pulses for their diets and incomes.

Most of the world's beans come from small farms. (Image courtesy of Allan Hruska)

Most of the world's pulse crops grow on small plots of land tended by manual labor. Pulses sold in India, for example, come from more than 22 million individual farms. Those small operations tend to be far less efficient than the large mechanized farms that dominate agriculture in developed countries. Hruska highlighted this dichotomy with slides showing mechanized harvesters sweeping across enormous U.S. fields, contrasted with groups of men with traditional planting sticks poking seeds into a mountainside in Latin America.

Reducing poverty and hunger requires increased pulse production in poor countries, which will not be easy to achieve. "It's not simply a technology, it's not a new bean variety that's going to change things, it's really a whole enabling system," Hruska said.

In countries with efficient pulse farming, that enabling system includes strong private and public sector support, with enforceable contracts, appropriate machinery, weather monitoring, and price supports. Many poor countries lack all of those things. Instead, farmers there rely on traditional multi-crop planting systems and diverse varieties of seeds to reduce their risks. Ideally, policy makers will preserve the genetic diversity of indigenous seed strains while helping farmers move to more efficient, mechanized systems.

The pulse of the market

P.K. Joshi of the International Food Policy Research Institute continued the exploration of pulse farming, with an overview of global trends in supply and demand for pulses. Overall pulse consumption rose with the world's population over the past 30 years, but consumption per capita fell. Meanwhile, distributors have used market inefficiencies to exploit pulse farmers in poor countries; even when bean prices skyrocket for consumers, growers' profits often stagnate, with middlemen keeping the difference. "[Small farmers] don't have enough bargaining power, so they're not sharing the higher market prices either in the global market or the local market," Joshi said.

Some of the world's poorest countries rely most heavily on pulse crops. (Image courtesy of P.K. Joshi)

In developed countries, the land area planted in pulses has declined but yields have risen, illustrating the potential to improve productivity with better farming methods. Developing countries show the opposite trend, with yields declining and land area increasing—probably as a result of the tendency in those countries to grow pulses on marginal land. Higher quality farmland usually hosts more profitable cereal crops. The lack of insurance programs for pulses in many countries also leaves farmers vulnerable when these crops fail.

Low yields from small farms lead many poor and middle-income countries to import pulses from the U.S. and Canada; major importers such as India are therefore highly sensitive to price shocks. "If there is any shortfall in production of pulses in [North America], the prices will go up, which we are expecting this year in India, and it will adversely affect the importing countries," Joshi said.

Joshi argued that as demand for pulses increases and supply remains constrained, prices will continue to rise, with devastating effects for the world's poor. To avoid that outcome, he advocated more research to improve pulse strains and programs to promote better farming practices in developing countries.

Oldways is probably best known for creating the Mediterranean Diet Pyramid, adapting the graphic design of the USDA's previous food guide to the meals traditionally eaten around the Mediterranean. The so-called Mediterranean diet that includes this cuisine has been correlated with low rates of cardiovascular disease. The organization has produced similar healthy-eating guides based on Asian, Latin American, and African ethnic diets.

Pulses are a natural fit for Oldways. "We just promote pulses because they are so much a part of heritage diets all around the world. There are pulses in every traditional diet," Baer-Sinnott said.

The latest diet Baer-Sinnott and her colleagues have created is called African Heritage and is based on the traditional cuisines from the African diaspora. Oldways teaches a curriculum on this diet in more than 100 African-American communities. The course covers recipes and cooking techniques, and teachers receive scales, blood pressure cuffs, and tape measures. Baer-Sinnott told the audience that students have reported benefits such as weight loss and improved blood pressure and have changed their cooking habits to include more vegetables. "Heritage is a really great motivator for change. Diabetes is really not a part of [cultural] heritage, and neither is heart disease," Baer-Sinnott said. A related program for supermarket dieticians also helps promote heritage recipes in stores.

A question of taste

Richard Black presented the perspective of a major player in the food industry, PepsiCo. As one of the world's leading food and beverage companies, PepsiCo is focused on understanding the reasons people choose particular foods. He explained that the roles taste and nutrition play in food decisions change with different types of meals and times of day. At breakfast, most people value taste and nutrition about equally. Taste becomes more important at lunch, and even more so at dinner. Snack choices are almost entirely about taste. "The challenge then is trying to make products that are good for you that people are going to want to consume," Black explained.

Tensions and trade-offs influence consumer decisions relating to food choices. (Image presented by Richard Black courtesy of Q:Quest Inc., Joanna Castellano)

Sometimes, meeting that challenge simply requires better marketing. Black cited the example of a low-salt line of Ritz brand crackers. Initially, the company labeled the crackers as "Low Sodium," and the crackers were a commercial flop. In a last-ditch effort to save the idea, the marketing team suggested changing the label to "Hint of Salt." The new package—containing the same product—was a huge hit.

Besides good salesmanship, better supply chains will be needed for pulses to succeed. As earlier speakers had explained, most of the world's beans are grown on small farms from diverse strains of seeds. Such a system cannot provide the thousands of tons of highly consistent inputs that a major food processing operation demands. Black explained that the only way to remedy that problem is to form public–private partnerships to ensure that the needs of farmers, food companies, and consumers are met.

All together now

Laurette Dubé described the Pulse Innovation Partnership she and her colleagues have formed at McGill University. The goal of the partnership is to include pulses in healthier processed foods, a project that requires cooperation among food companies, producers, health researchers, and consumers. It's a tall order.

"The type of multi-stakeholder partnership that we need to address this, we are asking partners that don't necessarily want to work together to [collaborate]," Dubé said. In particular, health researchers often distrust the food industry, which many see as a major contributor to current unhealthy eating patterns. Nonetheless, Dubé explained that the industry's understanding of consumer behavior and business needs is crucial for change.

Partnership participants also need to account for changing tastes. Dubé provided an overview of the major generational differences in North America, from the aging Baby Boom population to the Millennials who are eclipsing them. Each group has its own priorities for food choices. Meanwhile, other continents have unique demographic divisions to which products sold globally must adapt. The McGill partnership seeks to bring behavioral science to bear on global food production and consumption. "Let's all work together in making commercially successful products, but also ... healthy pulse-based diets," Dubé said.

Improving consumers' food choices requires systemic change. (Image courtesy of Laurette Dubé)

Simply promoting work that has already been done could also help. Dubé pointed to projects that have tried to integrate food recommendations into clinical practice to prevent and reverse diabetes. Unfortunately, those efforts have not been publicized widely. The partnership is now publishing articles and organizing webinars to do so.

Panel discussion

After the presentations, Amanor-Boadu led a discussion with the panelists before opening the floor to the audience. Panelists bemoaned the interlocking problems of supply and demand: companies cannot make pulse-based products without a reliable supply of inputs, but growers are reluctant to increase bean production until the market demands it. The group agreed that all stakeholders in the pulse community will need to work together to break this impasse.

Members of the audience contributed additional ideas, such as building websites to distribute pulse recipes. In places like India where pulses come from millions of small farms, co-ops and other market mechanisms could help these small operations deal with large food companies, participants suggested.

Meeting organizer Julianne Curran closed the symposium with a call to action. "Achieving the ambitious goals of the International Year of Pulses will require a broad tapestry of efforts and partnerships and dedication and passion, and I think there's no shortage of those in this room," she said.