Drawing the Linkage Between Pulse Consumption and Disease Reduction - PulseResearch
April 24, 2017
Pulses have many health benefits worth paying attention to
Michelle Shepherd is a big fan of pulses.
A Registered Dietitian and the owner of a healthcare practice based in British Columbia, Shepherd has long been recommending pulses to her clients, many of whom suffer from chronic diseases including digestive disorders, diabetes, heart health, cancer, and polycystic ovarian syndrome.
“I absolutely recommend my clients build a variety of pulses into their diet, as there are so many benefits,” she says. “The high fibre content helps feed our healthy gut bacteria and balance blood sugars for good health. Pulses are also a great source of protein, which aids in managing appetite and cravings. Research on pulses shows that adding them to our diet is associated with healthier weights.”
Shepherd also says she has seen a pickup in consumer interest in pulses in recent years.
“We are definitely seeing pulses come back in to the realm of the everyday diet as they become trendier and consumers are more health focused, and there is a greater interest in sustainable food,” she says. “Here on the West Coast we are also seeing them on restaurant menus which helps give clients fresh ideas and raises their profile.”
Shepherd has long been studying the health benefits of pulses through nutrition research papers and educational conferences, but Saskatchewan Pulse Growers (SPG) wants to ensure that the message is getting out to the healthcare community — and consumers in general — more broadly.
SPG also wants to ensure that there are more and more professionals such as Shepherd working to spread the pulse story.
This is why one of the major focuses of the organization’s research program is to understand the impact of pulse consumption on metabolic diseases, says Director of Research and Development, Dr. Lisette Mascarenhas.
“We know that pulses are high in protein, fibre, and micronutrients, and research shows us that a link exists between pulse consumption and satiety, low glycemic index, lower cholesterol, better gut health, and heart health,” she says.
“A concrete body of evidence continues to build through clinical trials where we can demonstrate why and how pulses work. We are keen to educate consumers in North America about the benefits of pulses and why they should consume pulses.”
But how is this being done?
SPG’s development strategy includes several components, such as ensuring that scientific evidence is in place to support the messaging that people should eat more pulses, and engaging health professionals such as Shepherd, who are one of the key influencers on people’s diets.
“We want dietitians and physicians who consult patients on metabolic disorders to evaluate the inclusion of pulses in their patients’ everyday diet, similar to exercise now,” Mascarenhas says. “We are well on our way to building the evidence they need to get buy-in.”
SPG’s strategy also involves investing in research into how commercial food manufacturers could include pulses as ingredients in their food products.
Investing in Health Claims
Dr. Peter Jones has been a Professor at the University of Manitoba and the Director of the Richardson Centre for Functional Foods and Nutraceuticals, based in Manitoba, for more than a decade.
He is very familiar with the health benefits of pulses and the research around pulses and health benefits.
“The current evidence available to us supports a therapeutic relationship between pulse consumption and risk management for a number of diseases and physiological disorders,” he says, referring to research that has demonstrated the multitude of health benefits that come from consuming a pulse diet.
These benefits include a lowered risk of cardiovascular disease, reduced blood sugar levels, reduced blood pressure, and better control over body weight and body fat. Research has also shown that pulse consumption can improve other biomarkers such as hemoglobin A1C which is linked to diabetes. Recent research has also shown that pulses improve satiety and fullness.
Dr. Jones agrees with SPG that the next crucial step in developing new markets for pulses based on their health attributes is to communicate these research results to consumers, particularly in Canada and the United States, where regular pulse consumption is low. One way to transmit this information could be through health claims provided on food product labels.
“Existing and ongoing research is really addressing important research gaps, to strengthen the evidence that leads to health claims on pulses and pulse products,” he says.
Pulses as Ingredients
One of these research gaps, which Dr. Jones is currently addressing through SPG-funded research, is considering how different preparations of pulses (including dehulled, split, ground, flaked, fractionated, and puréed) can be included in foods to improve their health and marketing attributes.
For example, research has found that adding 25 per cent lentil flakes to oatmeal can improve the final food product’s fibre and protein content, while also reducing its environmental impact and carbon footprint — all attributes that today’s consumers are interested in.
“We have all these great products to pick from and we have got all sorts of different formulations
and fractions of those pulse products,” Dr. Jones says. “And then we have a whole myriad of different foods into which we can park those products. We can then test the health benefits of those and try to come up with candidates that really seem to do the job better than other candidates.”
The ultimate goal of this research is to extend the current knowledge base around pulses and pulse ingredients, in order to optimize the dose and combination of ingredients to allow for more commercial pulse products on the market.
More SPG-funded research from the University of Toronto aims to prove that pulse flours or pulse components could be used to produce bread that had low glycemic indices and still tasted good.
Led by Dr. David Jenkins, a Professor in the Department of Nutritional Sciences at the University of Toronto and the Canada Research Chair in Nutrition and Metabolism, and Dr. Cyril Kendall, a Research Associate in the Department of Nutritional Sciences at the University of Toronto, the research ultimately aims to position pulse breads as an alternative to wheat bread, offering advantages in cardiovascular disease and diabetes prevention and treatment.
This research has made significant progress in developing formulations and balancing ingredients that meet the health objectives set out without compromising taste.
Pulses for Disease Treatment and Prevention
Another valuable area of pulse research involves exploring the link between pulses and disease treatment and/or prevention, and to-date, plenty of SPG-funded research has proven positive links between the two.
For example, research from the University of Toronto has proven that pulses are a great food choice for anyone who suffers from diabetes or is at risk of developing it. According to the Canadian Diabetes Association, an estimated 5.7 million Canadians suffer from diabetes as of 2015, and that number is expected to increase by 44 per cent in the next decade.
This study, also led by Dr. Jenkins and Dr. Kendall, compared the effects of eating pulses daily, versus whole wheat products, on people with Type 2 diabetes over a three-month period. The results showed that the daily intake of pulses improved blood glucose control, reduced the total cholesterol and triglyceride levels, and reduced blood pressure and heart rate.
The researchers agree that these findings are significant.
“When we started glycemic index testing, pulses stood out as by far the most consistently low glycemic index food,” says Dr. Kendall. “We also found they lowered low-density lipoprotein-cholesterol and most recently we have seen a blood pressure lowering effect with pulses, even in people well treated with blood pressure medications.”
“Pulses, therefore, hit all the chronic disease related targets. Combine that with their excellent protein, fibre, and mineral content, all in a food that is also good for the environment in that its root bacteria fix their own nitrogen, and there can surely be no other food better suited to the 21st century and beyond.”
Dr. Jenkins and Dr. Kendall’s research team has since gone on to share these results at dozens of food, nutrition, and scientific conferences across North America, and in articles published in renowned scientific journals. They have also used these results to leverage funding for more related research.
Dr. Jenkins, who is also famous in the science and nutrition communities for having developed the glycemic index in 1981, has also included pulses on his top 10 list of healthy foods, based on his research findings.
More SPG-funded research from the St. Boniface Hospital Research Centre in Winnipeg also examined the link between pulse consumption and lowered diabetes risk, by examining the role that lentil consumption played in improving glucose tolerance and decreasing cardiovascular disease risk in overweight individuals with high blood cholesterol.
The results of this research showed that the lentil diet was associated with better overall control of blood glucose levels, which could delay the progression to pre-diabetes (or metabolic syndrome) and Type 2 diabetes in at-risk individuals. Further research is being done to refine these results.
Other research from Dr. Jones’ lab is exploring the energy release action related to pulses, and its ensuing benefits.
“You see what happens to kids at Halloween when they eat very fast absorbed carbs,” Dr. Jones says. “Pulses slow down that rate of release of blood glucose.”
The research will examine the effect of eating food products containing pulses before a workout, in relation to aerobic endurance, insulin, blood glucose, appetite, and food intake post-workout. The hypothesis is that consuming pulse-based foods will have a positive effect in all these areas.
And although it is too early to have any results from the project, Dr. Jones believes the research will yield more important information about how pulses and pulse fractions can slow down the rate of release of blood sugar and control insulin, particularly in peoplewho might have a pre-disposition to Type 2 diabetes.
Overall the goal of all this research is to encourage more consumers to eat more pulses. This will create a new, high-value area of demand for Saskatchewan grown pulses. Currently Pulse Canada estimates that only 13 per cent of Canadians consume pulses on any given day and SPG hopes to see that number increase, Mascarenhas says.
“We want to educate every single consumer in North America about the benefits of pulses and why they should consume pulses.”
For a list of ongoing SPG-funded research, download the magazine.