Wrinkled Peas May Have More Health Benefits

LONDON - Oct 27/20 - SNS - Researchers in the United Kingdom believe some new varieties of marrowfat peas could deliver more health benefits than smooth peas because they contain higher levels of resistant starch, preventing sugar spikes in the body after meals.

The work by scientists at Imperial College London, the John Innes Centre, Quadram Institute Bioscience and University of Glasgow, suggests eating whole wrinkled peas or flour produced from them could help people avoid developing type 2 diabetes because sugar spikes after eating are thought to increase the risk of developing the disease.

Dr Katerina Petropoulou, first author of the research from the Centre for Translational and Nutrition Food Research at Imperial College London, notes, "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 researchers said larger, mature wrinkled peas contain higher levels of resistant starch than immature wrinkled peas or smooth round peas. That type of starch is more resistant to digestion, which the body breaks down to release sugar. Resistant starch breaks down slowly, reducing the speed by which the body releases sugar into the blood stream during digestion, resulting in a more stable increase rather than a spike.

Over a series of experiments, researchers gave healthy volunteers a mixed meal including 50 grams of wrinkled peas, and in a series of control experiments gave them regular smooth peas. Working with the University of Glasgow, researchers also added a tracer molecule to the peas, so that they could trace how they were absorbed and digested by the human gastrointestinal tract.

Previous research from the same group suggested that as bacteria in the digestive system ferment the starch, they produce short chain fatty acids which help boost the function of cells that produce insulin, again helping control blood sugar levels.

The researchers are now planning further trials involving volunteers with early stage type 2 diabetes. This will also involve a major pea breeding program with help from industry partners to develop more 'super peas' with the resistant starch. They will also explore the genetic background of commonly consumed pulses (beans) to see if similar genetic variation in other crops shows the same positive effects on health.

Professor Claire Domoney of the John Innes Centre in Norfolk said, "This research has emphasized the value of developing the pea lines used in this study, which could be compared meaningfully and involved many years of breeding. It also demonstrates how plant genetics can be used effectively across many disciplines to study the impact of food on human health.

"Longer term it could become policy to include resistant starch in food. We have precedents for this kind of intervention, such as iron being added to bread to tackle anaemia. It could potentially be policy that food should contain a certain amount of resistant starch to tackle type 2 diabetes and other metabolic illnesses."