Diets High in Red and Processed Meat Linked to Colon Cancer, Study Finds

Now that the Fourth of July is over, may want to reconsider what the classic American diet full of red and processed meat is doing to your health. A new study just published in the journal Gastroenterology suggests that a diet high in red and processed meat is linked to a higher risk of colon cancer.

Researchers from Brigham and Women’s Hospital in Boston examined data from over 134,000 participants (collected in two nationwide cohort studies) to determine how the intestinal microbiota was affected by the traditional Western diet, high in meat. The researchers compared dietary patterns and Escherrichiacoli (E. Coli) bacteria levels that showed up in colorectal tumors and found that the nutrient-poor Western diet stimulates the cancer-inducing colibactin – a substance derived from E. Coli.

Colon Cancer is the Third-Leading Cancer in the US and the Second Most Deadly

Currently, colon cancer is the third most common and second deadliest cancer in the United States, claiming over 50,000 lives every year. This recent study offers significant guidance in how to eat to prevent potential future colon cancer diagnoses. When examining the bacterial strains known as polyketide synthase (pks), the team found that the colorectal cancer patients following a Western diet showed higher levels of pks+ E. Coli, which led them to see the connection between meat-eating, this strain of bacteria, and the potential growth of tumors.

"These findings support our hypothesis that Western-style diets increase colorectal cancer risk through its effect on pks+ E. coli," Shuji Ogino, MD, Ph.D., MS, lead author of the study from the Program in Molecular Pathological Epidemiology in the Department of Pathology at the Brigham, said. "This is the first study to link the Western diet with specific pathogenic bacteria in cancer. Our next question is which component of western-style diet and lifestyle relates to colorectal cancer containing this bacterial species."

Improving Cancer Prevention Methods

The study also notes that the Western or American diet can cause intestinal inflammation – a common precursor to colorectal tumors. The conventionally unbalanced diet leads to many risks for patients, and now, this study joins a growing body of research that also links E. Coli and associated bacteria to colorectal cancer risk factors. The research teams hope that this study will encourage prevention methods through dietary change.

“As a society, we do not generally recognize the importance of prevention. Rather, we always regret after harms happen (e.g., cancer occurs),” Ogino told Medical News Today. “We need to change our mindsets and become proactive. Media is very hot about new treatment for end-stage cancer patients, which may prolong life for a few months. While this is important, it is much better to prevent. If we can prevent 10 percent of colorectal cancer cases, 150,000 new CRC cases each year — in the U.S. — would become 135,000 new CRC cases. You can see 15,000 people each year do not need suffer side effects of treatment or surgery. This would be a big impact.”

This research also considered other factors including body mass index, tobacco consumption, family history, physical activity, and alcohol consumption. The study authors noted that much more research is needed to appropriately determine the risk factor levels and how the American diet influences the microbiota over time.

Meat Heavy Diets Linked to Several Deadly Diseases

Last summer, the Physicians Committee for Responsible Medicine filed a lawsuit that requested California to add processed meats to the carcinogen list. This move highlighted the increasing understanding that the meat central to American diets could increase cancer risks significantly. One recent study from this March suggested that giving up meat lowers your risk of cancer by 14 percent. This research adds to the body of research that shows that plant-based diets can lower your risk of dying from several causes of mortality.

Convincing Americans to eat less meat is a difficult task, but the research is increasingly showing how red meat consumption is deadly. One study found that red meat consumption raises the risk of fatal heart disease by 18 percent. By reducing meat consumption or adapting the Western diet with healthier alternatives, Americans can improve prevention methods for several diseases.

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