Making Sure You Have a Pulse
Pulses are part of the legume family, but the term refers to only the dried seed. Therefore, all pulses—dried beans, chickpeas, lentils, lupins, and so on—are legumes, but not all legumes are pulses (e.g., peanuts, green peas, green beans, edamame, etc.). A nitrogen-fixing crop, pulses are very nutritious foods: They are rich sources of fiber, vitamins and minerals, beneficial phytochemicals, and high quality protein. The United Nations General Assembly declared 2016 the International Year of the Pulse, and the information presented during session 040, “A Dietary Staple for the 21 Century: Celebrating 2016, the International Year of Pulses,” on Monday, July 18, provided the rationale for this declaration.
David Jenkins of the University of Toronto has been a vegetarian since he was 12 years old and a vegan for the past 10 years. Because the protein content of pulses complements the protein content of other vegetarian foods, such as wheat and rice, Jenkins has been consuming beans for many years. Jenkins, who is also a physician, has other reasons for consuming pulses on a regular basis: Pulses reduce blood pressure and serum cholesterol and are associated with decreases in the risks of type 2 diabetes and heart disease.
His colleague at the University of Toronto, John Sievenpiper, concurs. Sievenpiper said that pulses may be a nutritional model of acarbose, an anti-diabetic drug. In the fight against type 2 diabetes and heart disease, this is extremely important. Sievenpiper said that the prevalence of type 2 diabetes has reduced the advances made in reducing mortality from cardiovascular disease: People who have type 2 diabetes are more likely to have cardiovascular problems leading to heart attacks and death. Studies being conducted at the University of Toronto indicate that pulses have protective cardiometabolic properties. For this and other reasons, Sievenpiper said that a shift is occurring in the clinical approach to diabetes, heart disease, and other noncommunicable diseases: Physicians are increasingly recommending adjustments to food intakes and dietary patterns.
These recommendations take into account the advice conveyed in the 2015 Dietary Guidelines for Americans. Joanne Slavin of the University of Minnesota explained that the dietary guidelines utilize systematic scientific reviews, meta-analyses and scientific reports, dietary data analyses, and food pattern modeling analyses. She pointed out that the 2010 Dietary Guidelines placed less emphasis on pulses because there was limited evidence to establish a clear relationship between pulse consumption and lower serum cholesterol. In addition, “pulses are unique foods as they fit as both a vegetable and protein in USDA dietary guidance,” she said. The studies being conducted at the University of Toronto help provide more data on the benefits of eating pulses, which is why there is greater emphasis on dry beans and peas in the 2015 version of the guidelines. Nevertheless, “consumption of pulses remains low and below recommended levels in the U.S.,” Slavin said.
Sievenpiper provided an anecdote that should encourage everyone to eat more pulses. His patient, a 74-year-old male, had hypercholesterolemia and ate a diet high in red meat and low in vegetables and fruits. Sievenpiper told the man to eat more nuts, viscous fiber, fruit, and vegetables—particularly vegetable proteins. To date, the man has experienced weight loss as well as a 70% reduction in his LDL cholesterol. From this and other evidence, Sievenpiper is pretty sure that a diet that incorporates regular intake of pulses results in clinically meaningful improvements in glycemic control (comparable to that with acarbose) as well as blood lipids, blood pressure, and body weight. But of course, Sievenpiper emphasizes that more research is needed; Slavin and Jenkins agreed. Regardless, pulses are clearly unique and special foods.