How a High-Fat Diet Increases Colon and Rectal Cancer Risk Has Been Discovered

Unhealthy eating was known to increase colorectal cancer risk, but the underlying biological mechanism was unclear. According to a newly published study, high-fat foods support cancer stem cell growth. Following this development, we hope those recommending a high-fat diet or saying “you can eat as much fat as you like as long as you do not consume carbohydrates” will reconsider their statements.

Colorectal (colon and rectal) cancers are the 3rd most common cancer type in women and men in our country. In the digestive system, the large intestine follows the small intestine. Its long initial section is the colon, and its final 15 cm is the rectum. Factors increasing colorectal cancer risk include a low-fiber diet, a sedentary lifestyle, obesity, hereditary transmission (%10) and a high-fat diet.

In this study, researchers created colorectal cancer models in mice to examine cancer stem cells and metastasis -producing cancer cells.

According to the Research Results:

• Mice fed a high-fat diet showed increased numbers of cancer stem cells and larger tumors in their intestines. Interestingly, the study emphasized that this effect of a high-fat diet was independent of obesity. Thus, a high-fat diet and obesity may be two independent risk factors for colorectal cancer.
• A cellular signaling pathway called JAK2-STAT3 was identified as triggering the growth of cancer stem cells in the large intestine following a high-fat diet. It is important to emphasize that cancer stem cells are the principal cells responsible for metastasis.
• In the experiment on mice fed a high-fat diet, inactivation of this signaling pathway was also observed to stop cancer stem cell growth.

What Does This Study Mean Clinically?

This is the first study to explain the biological mechanism linking colorectal cancer and a high-fat diet. Discovering how a high-fat diet affects the cellular signaling pathway that triggers tumor growth may enable the development of new-generation drugs. Targeted drugs blocking the JAK2-STAT3 signaling pathway may be effective. The study also provides important information about how environmental factors such as diet affect cancer stem cell growth.

The first question that comes to readers’ minds with articles like this will be “You ban everything, so what are we supposed to eat?” First, we would like to state that we avoid the word “ban” regarding nutrition. I have forbidden very few foods to my patients so far (and those were because of certain drug interactions during chemotherapy). Some fats are, of course, healthier than others, but this does not mean you can consume them in very large quantities... Our basic nutritional principles are a diet balanced in carbohydrates, fat and protein; reducing ready-made / fast food as much as possible; eating less overall (taking in less daily energy); reducing meat and increasing vegetables and fruit; and integrating an active lifestyle / exercise with appropriate nutrition.