Western Diet Increases Colon Cancer Risk Via Gut Flora - Healing Practice

Western diet increases colon cancer risk

A high consumption of red and processed meat, sugar and refined carbohydrates is typical of the diets of Western industrialized countries such as Germany and the United States. According to a recent study, this association seems to have a negative effect on the composition of the intestinal flora, which increases the risk of colon cancer.

A working group from Brigham and Women's Hospital in Boston, Massachusetts (USA) was able to use data from more than 134,000 participants to prove that a Western diet is associated with an increased risk of colon cancer. The cause of the increased risk appears to be adverse changes in certain gut bacteria, the team reports in the journal Gastroenterology.

Intestinal bacteria analyzed in intestinal tumors

There were over 1,000 cases of colon cancer among the subjects. The researchers analyzed the genome of certain intestinal bacteria present in intestinal tumours. These were special strains of the common gut bacteria Escherichia coli.

Harmful protein found in gut bacteria

The strains of E. coli found in the tumors carried a specific protein which is technically known as polyketide synthase (pks). Gut bacteria containing this protein were especially common in people whose diets were high in sugar, red and processed meat, refined carbohydrates and white flour products.

Polyketide synthase promotes mutations

The presence of. coli with pks was in turn associated with an increased risk of developing colorectal cancer. As the researchers point out, pks encodes an enzyme that has been shown to promote mutations in human cells.

However, the presence of strains of E. coli without pks was not associated with an increased risk of developing colorectal cancer.

Western diet promotes pks in gut bacteria

According to study author Dr. Overall, the study results support the hypothesis that the Western diet increases the occurrence of Escherichia coli with polyketide synthase, resulting in an increased risk of developing colorectal cancer.

First study of its kind

"This is the first study to link Western diets to specific pathogenic bacteria in cancer," said Dr. Ogino. In another study, the working group now wants to clarify which components of the Western diet most promote the formation of harmful proteins in intestinal bacteria. (vb)

Author and source information

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This text corresponds to the specifications of the specialized medical literature, medical guidelines and current studies and has been verified by health professionals.


Graduate editor (FH) Volker Blasek


Kota Arima, Rong Zhong, Tomotaka Ugai, et al. : Western-style diet, pks Island-Carrying Escherichia coli and colorectal cancer: analyzes of two large prospective cohort studies; in: Gastroenterology (2022), gastrojournal.org. Brigham and Women's Hospital: Microbial Link Between Western-Style Diet and Colorectal Cancer Incidence Discovered (Published: 06/27/2022), eurekalert.org

Important Note:
This article contains general advice only and should not be used for self-diagnosis or treatment. It cannot substitute a visit to the doctor.