NMU 109 – Newly Discovered Mechanism Explaining Link Between Overweight and Colon Cancer Development
Nutrition / Natural Medicine Update No 109 (October 17, 2018)
with Dr. James Meschino
Topic: Newly Discovered Mechanism Explaining Link Between Overweight and Colon Cancer Development
Source: Journal: Cancer Epidemiology Biomarkers & Prevention (October 2018)
Today I am citing a research paper published on October 11, 2018, in the journal Cancer Epidemiology Biomarkers & Prevention. The research helps to further explain the link between being overweight and the increased risk of developing colon cancer. We have known for some time that as a person’s body fat increases we see higher levels of two inflammatory chemicals in their blood, which are known to promote the development of inflammation and cancer in the body. These two chemicals (cytokines) are Tumor Necrosis Factor – alpha (TNF) and Interleukin-6 (IL-6). Regarding colon cancer, no one was sure if being overweight resulted in higher TNF and IL-6 concentrations within the colon cells, themselves. So, in this study researchers examined the colon cells of 16 lean individuals and 26 moderately overweight individuals (Body Mass Index at or above 34 – moderately overweight, as a BMI of 20-25 is the ideal range). The results showed that the colon cells of the overweight subjects had TNF and IL-6 levels that were 3-fold and 1.6-fold higher than the lean subjects. And the more overweight the person was the higher tended to be the TNF and IL-6 concentrations within their colon cells (colon mucosal cells).
Both TNF and IL-6 are known to promote cancer development, and once cancer cells have been created TNF and IL-6 also act to promote the growth, replication, and metastasis of those cancer cells – making cancer more aggressive. In fact, examination of the cancer microenvironment has shown conclusively that TNF and IL-6 are key drivers in the development and progression of cancer within the body. As TNF and IL-6 also promote the inflammatory process, it helps to also explain the strong link between chronic inflammation and increased risk of cancer. The researchers of this study conclude that being moderately overweight was associated with higher concentrations of TNF and IL-6 within colon cells, which in turn modulates the expression of key genes known to trigger pathways and mechanisms that promote the development and metastasis of colon cancer.
I think this is something we should pay attention to, as in North America and much of Western world colorectal cancer is the third most common cancer and the second leading cause of death among cancers that affect both men and women. The American Cancer Society reports that the overall lifetime risk of developing colorectal cancer is about 1 in 22 for men and 1 in 24 for women. Some reports show that 70-90% of colon cancer is avoidable via better dietary and lifestyle practices (J Natl Cancer Institute 1996 Willettt W). Achieving and maintaining a more ideal body weight is emerging as one of the key factors in the prevention of this disease.
Of course, undergoing a colonoscopy and early screening for colon cancer after age 50 is also critical to identifying early-stage colon cancer, which is curable in a high percentage of cases. Nevertheless, preventing colon cancer development in the first place should be one of your lifetime wellness goals and we are learning more and more dietary and lifestyle strategies to help make that a reality.
I have included the research study citation in the text below.
Pfalzer AC, Leung K, Crott JW, Kim SJ, Tai AK et al. Incremental elevations in TNF-alpha and IL-6 in the human colon and precancerous changes in the mucosal trascriptone accompany adiposity. Cancer Epidemiology Biomarkers & Prevention. DOI: 10.1158/1055-9965.EPI-18-0121 Oct 11, 2018.
2. IL-6 and Cancer:
Kumari N et al. Role of interleukin-6 in cancer progression and therapeutic resistance. Tumour Biiol. 2016. 37(9):11553-11572
3. Colon Cancer Statistics:
Science Daily: Inflammatory proteins in colon increase incrementally with weight:
Eat Smart, Live Well, Look Great,