A type of wrinkled pea may help control blood sugar levels and could reduce the risk of type 2 diabetes, a study suggests.
Scientists say incorporating the “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 type of pea which, unlike regular smooth peas, contains higher amounts of resistant starch which takes longer for the body to break down.
According to the study, compared with eating smooth peas, wrinkled peas prevented sugar spikes – where blood sugar levels rise sharply after a meal.
The same effect was seen when consuming flour made from wrinkled peas incorporated in a mixed meal.
Researchers suggest this could be important as frequent, large sugar spikes are thought to increase the risk of diabetes.
They add 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.
Dr Katerina Petropoulou, first author of the research from the Centre for Translational and Nutrition Food Research at Imperial College London, 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.”
The peas used in the research, published in Nature Food, are similar to frozen peas available to buy in supermarkets.
They are also the same as those used by scientist Gregor Mendel in the 1800s to show how dominant and recessive genetic traits can be passed on through selective breeding.
However, in these latest experiments, researchers at Imperial College London, the John Innes Centre, Quadram Institute Bioscience and the University of Glasgow used larger, mature versions of those typically found in the freezer aisle.
Larger, mature peas contain more so-called resistant starch.
This is due to the way the starch is made in the cell, and the fact that the cells themselves are more resistant to digestion.
The body breaks down starch to release sugar, but resistant starch is broken down more slowly, so sugar is released more slowly into the bloodstream.
This results in a more stable increase rather than in a spike, the researchers say.
In the latest study, they used a type of “super pea” (Pisum sativum) – wrinkled peas with a naturally occurring genetic mutation that produces a greater amount of resistant starch, but a lower overall carbohydrate content.
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.
The researchers also added a tracer molecule to the peas, so they could trace how they were absorbed and digested by the human gastrointestinal tract.
The experiments were repeated using flour made from wrinkled peas or control 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 control 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.
And 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 how the peas were prepared and cooked affected how quickly they were digested.
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.