Processed meats cause colorectal cancer.
Colorectal cancer is the second most commonly diagnosed cancer and the second leading cause of death from cancer among Canadians (1). In 2015 the World Health Organization (WHO) released a report, classifying “processed meat” as a carcinogen that significantly increases the risk of developing colorectal cancer (2). Red meats were also noted to be potential carcinogens. These findings raised questions about what the underlying mechanisms may be.
Inflammation may be the underlying mechanism leading to cancer.
Early in 2018, a new study was published in the journal JAMA Oncology, suggesting that processed meats and other foods may be increasing the risk of colorectal cancer by inducing inflammation (3). “Chronic inflammation” has been associated with cancer in general and there have been studies specifically associating it with colorectal cancer.
To further investigate this idea, researchers looked at dietary patterns that were known to be pro-inflammatory. More specifically, foods groups were classified using the Empirical Dietary Inflammatory Pattern (EDIP), which assessed the inflammatory potential of foods on a continuum from extremely anti-inflammatory to pro-inflammatory. In other words, a lower score was given to anti-inflammatory foods and a higher EDIP score was given to pro-inflammatory foods. Based on this assessment, the researchers classified the following as pro-inflammatory foods: processed meat, red meat, organ meat, sugar beverages and refined grains. Accordingly, the 121 050 participants in the cohort study were assessed for their dietary intake over a period of 26 years, where questionnaires were completed every four years.
Reviewing these results, the researches found that men and women consuming a pro-inflammatory diet were 44% and 22% more likely to develop cancer, respectively. These findings were consistent with previous research linking inflammation to cancer development. Hence, it was inferred that inflammatory responses might be an underlying mechanism contributing to the development of colorectal cancer. Of course, this needs to be further investigated.
Take these results with a grain of salt!
While these findings may be of significant value, it is important to recognize that there are many factors in the diet that could either promote or inhibit the risk of cancer. Therefore, this study is by no means suggesting that these foods are the single contributors to cancer. As mentioned, further investigation is necessary.
Here’s the good news:
There are things you can do to manage chronic inflammation. Weight management, regular physical activity and diet are all factors that can be modified through lifestyle changes. A great dietary pattern to con
sider is the Mediterranean diet, which has been well researched to provide numerous health benefits. Focusing on inflammation, this diet emphasizes foods that are “anti-inflammatory”, such as vegetables, fruits, and healthy fats.
- Canadian Cancer Society. (2018). Colorectal cancer statistics. Retrieved from http://www.cancer.ca/en/cancer-information/cancer-type/colorectal/statistics/?region=on
- World Health Organization. (2015, October 29). Links between processed meat and colorectal cancer. Retrieved from http://www.who.int/mediacentre/news/statements/2015/processed-meat-cancer/en/
- Tabung, F. K., Liu, L., Wang, W., Fung, T. T., Wu, K., Smith-Warner, S. A., … & Giovannucci, E. L. (2018). Association of Dietary Inflammatory Potential With Colorectal Cancer Risk in Men and Women. JAMA oncology.