Cancer Prevention with Resistant Starch

A trial in people with a high hereditary risk of a wide range of cancers has shown a major preventive effect from resistant starch, found in a wide range of foods such as oats, breakfast cereal, cooked and cooled pasta or rice, peas, beans, and slightly green bananas.

An international trial - known as CAPP2 – involved almost 1000 patients with Lynch syndrome from around the world and revealed that a regular dose of resistant starch, also known as fermentable fiber, taken for an average of two years, did not affect cancers in the bowel but did reduce cancers in other parts of the body by more than half.

This effect was particularly pronounced for upper gastrointestinal cancers including oesophageal, gastric, biliary tract, pancreatic, and duodenum cancers.

The astonishing effect was seen to last for 10 years after stopping taking the supplement.

The study, led by experts at the Universities of Newcastle and Leeds, published today in Cancer Prevention Research, a journal of the American Association for Cancer Research, is a planned double-blind 10 year follow–up, supplemented with comprehensive national cancer registry data for up to 20 years in 369 of the participants.

Previous research published as part of the same trial revealed that aspirin reduced cancer of the large bowel by 50%.

"We found that resistant starch reduces a range of cancers by over 60%. The effect was most obvious in the upper part of the gut," explained Professor John Mathers, professor of Human Nutrition at Newcastle University. "This is important as cancers of the upper GI tract are difficult to diagnose and often are not caught early on.

"Resistant starch can be taken as a powder supplement and is found naturally in peas, beans, oats, and other starchy foods. The dose used in the trial is equivalent to eating a daily banana; before they become too ripe and soft, the starch in bananas resists breakdown and reaches the bowel where it can change the type of bacteria that live there.

"Patients with Lynch syndrome are high risk as they are more likely to develop cancers so finding that aspirin can reduce the risk of large bowel cancers and resistant starch other cancers by half is vitally important.

"Based on our trial, NICE now recommends Aspirin for people at high genetic risk of cancer, the benefits are clear – aspirin and resistant starch work."

Ref: John C. Mathers, Faye Elliott, Finlay Macrae, Jukka-Pekka Mecklin, Gabriela Möslein, Fiona E. McRonald, Lucio Bertario, D. Gareth Evans, Anne-Marie Gerdes, Judy W.C. Ho, Annika Lindblom, Patrick J. Morrison, Jem Rashbass, Raj S. Ramesar, Toni T. Seppälä, Huw J.W. Thomas, Harsh J. Sheth, Kirsi Pylvänäinen, Lynn Reed, Gillian M. Borthwick, D. Timothy Bishop, John Burn; on behalf of the CAPP2 Investigators, Cancer Prevention with Resistant Starch in Lynch Syndrome Patients in the CAPP2-Randomized Placebo-Controlled Trial: Planned 10-Year Follow-up. Cancer Prev Res (Phila) 2022; https://doi.org/10.1158/1940-6207.CAPR-22-0044