Leah Berenson
Leah Berenson
February 18, 2024 ·  4 min read

Dietary Supplement Cuts Risk of Hereditary Cancer by 60%, Scientists Find. 

Cancer is a disease that causes much discomfort, both emotionally and physically. According to the CDC, it is the number two killer in the United States behind heart disease, so it is no wonder that doctors and scientists invest so heavily into research. The drive to find more effective cancer treatment options and possible preventive measures is always ongoing. Recently, scientists discovered that a fiber-like compound, which is also available as a dietary supplement, might be an effective preventive measure in those with a condition that predisposes them to a higher risk of developing cancer. In around 60% of cases, the fiber-like food compound appeared to reduce the risk of certain hereditary cancers. What was this food compound? Resistant starch. It is naturally found in green bananas, beans, legumes, and cooled rice, and pasta.

Resistant Starch Trial  

The trial spanned 20 years, with almost 1,000 participants from around the world. It was called the CAPP2 Study where 918 participants suffering from Lynch Syndrome were assigned to one of two groups. One group consisted of 463 participants and the other, 455. The larger group was given a 30-gram dose of resistant starch, daily for 2 years.

Meanwhile, the smaller group was given a placebo that mimicked the look of the powdered starch, without the active ingredients. Ten years later researchers followed up and the results were impressive. It appeared as if the starch supplement had done wonders. Among the patients who had taken the placebo, there were 21 new cases of upper GI cancer, whereas the group who’d taken the resistant startch dietary supplement only had 5. The results of this study were so remarkable that scientists stressed that they needed to be replicated to make sure they weren’t missing anything.

“The results are exciting, but the magnitude of the protective effect in the upper GI tract was unexpected, so further research is required to replicate these findings,” said Tim Bishop, a genetic epidemiologist from the University of Leeds.

John Mathers, a professor of Human Nutrition at Newcastle University said “We think that resistant starch may reduce cancer development by changing the bacterial metabolism of bile acids and to reduce those types of bile acids that can damage our DNA and eventually cause cancer. However, this needs further research.” [6]

Although the risk to only the upper GI was reduced from the use of the resistant starch supplement, scientists tested another substance to see its effects. The test was done during the same trial and the results were published in 2020. Aspirin, which has been said to prevent heart attacks is now being looked at to prevent cancer as well in those with Lynch syndrome as well. The results showed Aspirin had an impact on lower GI cancers by reducing risk of bowel cancers in participants by around 50%.

Geneticist at Newcastle University said, “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 [the UK’s National Institute for Health and Care Excellence] now recommends Aspirin for people at high genetic risk of cancer, the benefits are clear – aspirin and resistant starch work.”[6]

What is Lynch Syndrome?

Lynch Syndrome, according to the American Society of Clinical Oncology, is “a type of inherited cancer syndrome associated with a genetic predisposition to different cancer types. This means people with Lynch syndrome have a higher risk of certain types of cancer. Lynch Syndrome is also known as hereditary non-polyposis colorectal cancer (HNPCC).”[7]

What is Resistant Starch?

A dietary supplement is a natural vitamin or nutrient that enhances the nourishment intake of one’s daily diet. Dietary supplements support good health and give bodies a dose of herbal properties thought to improve overall function. Resistant Starch, “passes through the small intestine and then ferments in the large intestine, where it feeds beneficial gut bacteria.[4] It is found in foods such as oats, slightly green bananas, pasta, rice, peas and beans. It can also be purchased from a supplement or health food store as a fiber-like substance.[4]

Although this trial was done specifically on people with high risk of cancers due to genetics, it still gave an in depth insight to how some cancerous cells respond to everyday dietary supplements. Resistant starch can protect against certain cancers and that means there may be other everyday solutions just waiting to be discovered. 


  1. Cancer prevention with aspirin in hereditary colorectal cancer (Lynch Syndrome), 10-year follow-up and registry-based 20-year data in the CAPP2 study: A double-blind, randomised, placebo-controlled trial.” The Lancet. Prof John Burn, MD, et al. Retrieved September 20, 2022.  
  2. What is cancer?National Cancer Institute. Retrieved September 20, 2022.
  3. What is a dietary supplement?Quality Supplements. Retrieved September 20, 2022.
  4. Dietary supplement cuts risk of hereditary cancer by 60%, scientists find.” Science Alert. Retrieved September 20, 2022
  5. Cancer prevention with resistant starch in Lynch syndrome patients in the CAPP2-randomized placebo controlled trial: Planned 10-year follow-up.” American Association for Cancer Research. John C. Mathers, et al. Retrieved September 20, 2022.
  6. First trial to prove a diet supplement can prevent hereditary cancer. Press Office. Retrieved September 20, 2022.
  7. Lynch syndrome.” Cancer.Net. Retrieved September 20, 2022.