0554 GMT November 27, 2020
Scientists have said incorporating "super peas" into foods in the form of whole pea seeds or flour may help tackle the global type 2 diabetes epidemic.
The research focused on a naturally occurring wrinkled pea which, while genetically identical to the regular smooth peas often found in supermarket frozen food aisles, contains higher amounts of so-called resistant starch due to a natural mutation.
"If peas were not harvested fresh for freezing, but allowed to mature on the plants, it is likely that many would develop into wrinkled seeds," said Dr. Katerina Petropoulou, of the Center for Translational and Nutrition Food Research at Imperial College London and first author of the research.
The body breaks down starch to release sugar but resistant starch is broken down more slowly, meaning sugar is released more slowly into the bloodstream. This results in a more stable increase rather than a "sugar spike" in which blood sugar levels rise sharply after a meal, researchers say.
The same effect was seen when consuming flour made from wrinkled peas incorporated in a mixed meal. Researchers suggested this could be important because frequent, large sugar spikes are thought to increase the risk of diabetes.
They added that flour from these peas could potentially be used in commonly consumed processed foods which, if eaten over the long term, could prevent these sugar spikes.
In the experiments, researchers at Imperial College London, the John Innes Center, Quadram Institute Bioscience and the University of Glasgow compared the larger, mature wrinkled peas, which produced a lower overall carbohydrate content, with normal peas.
The team gave healthy volunteers a mixed meal including 50 grams of wrinkled peas, and in a series of control experiments gave them regular peas. They also added a tracer molecule to the peas, so they could track how they were absorbed and digested by the human gastrointestinal tract.
The experiments were repeated using flour made from wrinkled peas or regular peas.
To further investigate the impact of long-term consumption, they recruited 25 volunteers and asked them to consume pea hummus and mushy peas made from wrinkled or regular peas for a period of four weeks.
Previous research from the same group suggested that, as these bacteria ferment the starch, they produce compounds called short chain fatty acids. These compounds help boost the function of cells that produce insulin, which helps control blood sugar.
Further tests using a mimic of the human gut showed that the way in which the peas were prepared and cooked affected how quickly they were digested.
Dr. Petropoulou said: "There is much evidence that diets rich in a type of carbohydrate called resistant starch have a positive impact on controlling blood glucose levels, and hence reduce susceptibility to type 2 diabetes."
Professor Pete Wilde, of the Quadram Institute, said: "This study has shown us that, by preparing these peas in certain ways, we can further reduce blood sugar spikes, opening up new possibilities for making healthier foods using controlled food processing techniques."
The researchers are now planning further trials involving volunteers with early stage type 2 diabetes.