Colorectal cancer is third on the list of the most common cancer diagnoses in the United States. An estimated 102,900 Americans will be diagnosed with colon cancer in 2010, according to the American Cancer Society. The exact cause of this form of cancer is not known. What is clear is that being obese -- and the lifestyle behaviors associated with excess weight -- raises your risk of developing colon cancer.
Causes
Excessive cell growth in the colon can lead to development of pre-cancerous cells. Groups of these cells form polyps in the lining of your colon and can eventually become cancerous if not removed. Having a family history of colon cancer also raises your risk due to inherited gene mutations. Some inherited conditions, including familial adenomatous polyposis and Lynch syndrome, increase your likelihood of having colon cancer at an earlier age. Keep in mind that a family history is not a guarantee that you will develop this form of cancer.
Symptoms
You may not have any symptoms during the beginning stages of colon cancer. Changes in your bowel movements, including constipation or diarrhea that continues for weeks, can be a sign of colon cancer. Look out for changes in the consistency or appearance of your stool as well, such as the presence of blood. Rectal bleeding is also a possible symptom to watch out for. You may experience abdominal pain, cramping or gas. Other signs include fatigue and unintended weight loss.
Obesity & Cancer Risk
Being obese increases your risk of developing colon cancer. Two primary factors that contribute to obesity also increase cancer risk: a sedentary lifestyle and an unhealthy diet. High-fat diets low in fiber may have a negative effect on colon health. Research suggests that a certain variation in the gene ADIPOQ not only increases your risk of obesity, but also ups the chance of colon cancer, according to a 2008 study published in the "Journal of the American Medical Association." This gene produces the hormone adiponectin, which has also been found to alter cell growth and play a role in tumor development.
Obesity & Treating Cancer
Obesity not only contributes to your cancer risk, but also affects the effectiveness of treatment. In fact, a 2010 study reveals that being obese increases your risk of dying from colon cancer from 19 to 35 percent, according to Mayo Clinic research published in the journal "Clinical Cancer Research." The study's findings show that being obese increased the risk that colon cancer would spread and reoccur. Another 2010 study published in "Cancer Epidemiology, Biomarkers & Prevention" finds that postmenopausal women who are obese prior to being diagnosed with colon cancer are at higher risk of dying from the disease.
References
- American Cancer Society: Colorectal Cancer: What Are the Key Statistics About Colorectal Cancer?
- MayoClinic.com: Colon Cancer
- University of Alabama at Birmingham: Colon Cancer Link to Obesity Uncovered
- Clinical Cancer Research: Obesity Is an Independent Prognostic Variable in Colon Cancer Survivors
- Cancer Epidemiology, Biomarkers & Prevention: Survival of Women with Colon Cancer in Relation to Precancer Anthropometric Characteristics: The Iowa Women's Health Study
