A cutting-edge study has found that resistant starch, found in common foods such as oats and especially green bananas, can significantly reduce the risk of developing certain cancers. The findings come from the CAPP2 trial, which involved nearly 1,000 people with Lynch syndrome from several countries. The study was carried out by experts at the Universities of Newcastle and Leeds in Australia.
Lynch syndrome, which affects around one in 300 people in the UK, is a genetic disorder that can significantly increase the risk of cancer, mainly bowel, womb and ovarian cancer. People living with the syndrome have up to an 80% chance of developing bowel cancer in their lifetime, in addition to being at risk of other cancers earlier than the general population.
A cutting-edge study has found that resistant starch, found in common foods such as oats and especially green bananas, may significantly reduce the risk of developing certain cancers
The results of the study showed that regular consumption of resistant starch, also known as fermentable fibre, over a two-year period had no effect on the incidence of bowel cancer. However, it was notable that this type of starch helped to reduce the incidence of cancers in other organs in the body by more than half.
This protective effect was particularly pronounced for cancers involving the upper digestive system, including those of the oesophagus, stomach, biliary tract, pancreas and duodenum. Notably, the protective effects of resistant starch persisted for up to 10 years after participants stopped taking the supplements.
The study, published in the journal Cancer Prevention Research, was conducted in a double-blind, randomized, double-blind study with a follow-up period of 10 years, with data collected from national cancer registries for up to 20 years for 369 participants.
Resistant starch is a type of carbohydrate that is not digested in the small intestine but is instead fermented in the large intestine, where it supports the growth of beneficial bacteria. Like fibre, resistant starch has many health benefits, but is also lower in calories than traditional starch.
Professor John Mathers, a leading nutrition researcher at Newcastle University, believes that resistant starch may reduce the risk of developing cancer by changing the way bacteria metabolise bile acids. He explains: “We think resistant starch may reduce cancer formation by modulating bacterial bile acid metabolism, thereby reducing the production of bile acids that can damage DNA and lead to cancer.” However, he also stresses that more research is needed to understand the mechanism.
Professor Mathers highlights the significant reduction in cancer risk associated with resistant starch, with findings suggesting that this carbohydrate can reduce the incidence of many types of cancer by more than 60%
In addition, research has shown that aspirin can reduce the risk of colon cancer by up to 50%, leading the UK National Institute for Health and Care Excellence (NICE) to recommend aspirin for people at high genetic risk of cancer.
Resistant starch can be obtained through natural foods such as peas, green bananas and oats, or as a powdered supplement. Professor Mathers highlighted the health benefits of resistant starch, not only because of its lower calorie content but also because of its potential to prevent cancer through modulating bile acid metabolism. However, he also asserted that further research is needed to confirm these benefits.
