Amelia Nichele
Amelia Nichele is a science journalist at The Royal Institution of Australia.
Don’t turn your nose up at wrinkled peas: they could be a life saver. A new study has found that a natural mutation in smooth green peas that causes them to become rather shrivelled looking could help control blood sugar levels and reduce the risk of type 2 diabetes.
Researchers in the UK say these “super peas” – and even flour made from them – prevent sugar spikes because they have high levels of resistant starch, which takes the body longer to digest while being lower in carbohydrates.
“The super pea contains a naturally-occurring variant gene that means they’re high in resistant starches,” says Gary Frost from Imperial College London, lead author of a paper in Nature Food. “These starches are not completely digested in the upper parts of the digestive tract and are available for fermentation by bacteria in the colon.”
The high amount of resistant starch 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 wrinkled peas used in the study were larger, more mature versions of the peas typically found in the supermarket – and which do, in fact, have the high-resistant starch trait. However, they’re grown for immature pea seed harvest, so they haven’t developed maximum amounts of starch.
Volunteers underwent a variety of tests across four controlled experiments. They were given either regular or wrinkly pea products, including food made with pea flour and pea hummus, without knowing which was which.
The peas were also fixed with a tracer molecule so the researchers could track how they were absorbed and digested.
“This research has emphasised the value of developing the pea lines used in this study, which could be compared meaningfully and involved many years of breeding,” says co-author Claire Domoney from the John Innes Centre.
“It also demonstrates how plant genetics can be used effectively across many disciplines to study the impact of food on human health.”
The researchers highlight that peas are not the only food known to have the resistant starch mutation, with other research focusing on breeding the mutation into staple crops such as rice and wheat.
“Longer term, it could become policy to include resistant starch in food. It could potentially be policy that food should contain a certain amount of resistant starch to tackle type 2 diabetes and other metabolic illnesses,” says Domoney.