Beans, Whole Grains in Diet Beneficial for Colorectal Cancer Survivors

A small randomized controlled pilot study points toward the multiple benefits of adding rice and beans to the diet of colorectal cancer (CRC) survivors. The research was presented at the American Association for Cancer Research (AACR) Annual Meeting 2017.¹

“The simple message is, ‘Food is medicine,’ and we are looking at how to simplify that and make it apply to our everyday lives,” says co-investigator Regina Brown, MD, of the University of Colorado School of Medicine in Aurora, in a news release.²

Increased dietary intake of beans and whole grains as part of the American Institute for Cancer Research (AICR) Recommendations for Cancer Prevention has been tied to a reduced burden of CRC. 

Erica Borresen, a research associate at Colorado State University in Fort Collins, and colleagues sought to examine changes in gut microflora and dietary intake in CRC survivors in the Beans/Bran Enriching Nutritional Eating for Intestinal health Trial (BENEFIT).

The study included 29 patients with a history of CRC who were randomly assigned to receive 4 weeks of meals and snacks that contained 30 grams/day of rice bran, 35 grams/day of navy bean powder, or neither.  

Compared with baseline, consumption of rice bran or navy beans was associated with increased nutritional measures including fiber, iron, folate, and B vitamins. Furthermore, both intervention groups demonstrated increases in gut bacteria diversity and richness compared with baseline.

Of note, the researchers observed reduced colorectal cancer cell growth when samples were treated with stool extracts from the rice bran and navy bean groups.²

“The evidence is there in animals and we can now study this in people. The question is, what are we doing to achieve adequate levels of intake of these foods? It’s not enough to say ‘I eat them once in a while.’ That’s not going to work, particularly if you are at higher risk. You have to meet a dose, just like you need a dose of a certain drug, you need to reach intake levels and consume increased amounts of these foods, and that’s where people, including me, are challenged. Not everyone wants to open up a can of beans and eat them every day,” said co-investigator Elizabeth Ryan, PhD, in a news release.²

Ryan continued, “I really feel that there’s hope in this being a practical solution to improve gut health and specifically colorectal cancer prevention.”

References

1. Borresen EC, Oppel RC, Brown DG, Brown RJ, Ryan EP. Increasing dietary rice bran and navy bean intake for colorectal cancer control and prevention: a randomized-controlled pilot investigation. Presented at: American Association for Cancer Research Annual Meeting 2017; April 1-5, 2017; Washington, DC. Abstract CT138/19.

2. Phase II trial: Rice bran adds microbiome diversity, slows growth of colon cancer cells [news release]. University of Colorado Anschutz Medical Campus; April 4, 2017. https://www.eurekalert.org/pub_releases/2017-04/uoca-pit040417.php. Accessed April 18, 2017.