A Health Trifecta - PulseResearch
April 25, 2017
Pulses good news for glycemic control and cardiovascular risk factors in Type 2 diabetes
Dr. David Jenkins is excited about pulses. That is because they are turning out to be a health trifecta.
“Pulses do three major good things – glucose reduction, cholesterol reduction, and blood pressure reduction,” Jenkins says. “You do not have many foods that can do that.”
It was actually while testing pulse diets on 120 non-insulin dependent diabetic men and postmenopausal women to determine glycemic control and cardiovascular risk factors that Jenkins and his team learned about the effect pulses had on blood pressure.
“It appears pulses have the potential to lower blood pressure,” he says. “This is possibly related to their protein content.”
The researchers believe their study, funded by Saskatchewan Pulse Growers, is the first to demonstrate a blood pressure reduction with legume consumption in Type 2 diabetic patients. Their results reveal the reduction was all the more remarkable since the mean starting blood pressure was already in the acceptable range at 122/72 millimetres of mercury (mmHg).
For the study, participants were encouraged to increase their pulse intake by at least one cup per day, or to increase insoluble fibre by eating whole wheat products, for three months. To determine their results, the researchers measured the participants’ change in hemoglobin A1c (HbA1c) values and determined a calculated coronary heart disease risk score.
The low-glycemic index pulse diet reduced HbA1c values by 0.5 per cent while the high wheat fibre diet reduced the values by 0.3 per cent. The respective coronary heart disease risk reduction on the low-glycemic index diet was 0.8 per cent, largely owing to a greater relative reduction in systolic blood pressure on the low-glycemic index pulse diet compared with the high wheat fibre diet.
The researchers believe it was the first study conducted to promote the use of pulses specifically as the major focus of a low-glycemic index diet for the management of diabetes. The study also highlights the quantities of pulses consumed.
“We determined we need 190 grams of cooked pulses a day for results,” says Jenkins. “We used Saskatchewan-grown pulses with lentils and chickpeas as the mainstay.”
The findings linking legume consumption to both improved glycemic control and reduced coronary heart disease risk are particularly important because Type 2 diabetes is increasing most rapidly in big cities of countries where pulse intake has traditionally been high, such as India and Latin America, but where now pulse free Western-type diets are common.
The researchers are interested in doing more work to see how pulses can impact blood pressure as the people in the diabetes study had normal blood pressure.
“We saw the interaction between diabetes and blood pressure and pulses there, now we want to see the relation without diabetes and just with blood pressure and pulses,” Jenkins says.
SPG Investment: $300,357
Project Length: 3.5 years
Co-Funder: Agriculture and Agri-Food Canada, Agricultural Bioproducts Innovation Program - $353,556
Project Lead: Dr. David Jenkins, MD - Canada Research Chair, Department of Nutritional Sciences, Faculty of Medicine, University of Toronto and St. Michaels Hospital