Prevent Colorectal Cancer

Colorectal cancer is an abnormal growth of cells in colon and rectum. It can start either in the inner lining of colon or rectum and grows toward center. In 2002, colorectal cancer was the third most frequently reported cancer in West Malaysia. In 2006, it was reported that male (56.5%) was higher with colorectal cancer compared to female (43.5%). In addition, Chinese had the highest reported to suffer with colorectal cancer. Most colorectal cancer begins in polyps and they can grow to form cancer. Thus, it is important to get early detection and remove the polyps.

Source: Colon Cancer, Wikipedia

There are lifestyle-related factors that are linked to the risk of colorectal cancer. Such as eating too much red meats and processed meats, lack of exercise, overweight or obese, smoking and heavy alcohol use. However, these factors are common to be written in all types of cancers. Specific factors to cause colorectal cancer are age, family history and inflammatory bowel disease. The occurrence of the cancer increases with age. In 2006, the percentage of colorectal cancer among 70 years old and above Malaysian in male and female is 28.7% and 30.5% respectively. Some studies show that nonsteroidal anti-inflammatory drugs such as aspirin can reduce the development of colorectal cancer. However, it is not recommended because it can increase the risk of bleeding. 

Again, the diet that being told in almost all cancer website are eat less fat, eat more fruits and even more vegetables, eat less red meat and processed meat, eat more fiber such as whole grains, reduce alcohol intake and the most important is to maintain normal weight. What about physical activity? It will be told by almost all doctors to increase the intensity and amount of physical activity.

A high intake of fiber has been thought to reduce the risk of colorectal cancer and adenoma. In a cohort study from The New England Journal of Medicine, the prospective study among women do not show the existence of an important protective effect of dietary fiber against colorectal cancer or adenoma. The researcher found no association between the intake of dietary fiber and the risk of colorectal cancer. This finding is strengthen with another study entitle ‘Dietary Fiber Intake and Risk of Colorectal Cancer’. Although high intake of fiber may not have a major effect on the risk of colorectal cancer, the dietary fiber from vegetables and fruits can be advised as to lower other chronic diseases such as heart diseases and diabetes.

In another study, the findings indicate that a higher consumption of fruit and vegetables may protect against the development of colorectal cancer and the association is stronger in non-smokers. It is recommended to eat variety color of vegetables. The colorful vegetable with red, orange and yellow pigments are chemically group of beta carotene. Beta carotene serves as antioxidant but it may enhance DNA oxidative damage when the cells are exposed to tobacco smoke. Again, stop smoking is very important among colorectal cancer patients. The substances in fruits and vegetables might increase the carcinogenic potential of tobacco smoke. It is nothing and gains no benefits if patients eat more fruit and vegetables but do not stop smoking.

It is very rare to find medical officers telling diabetic patients that diabetes can cause colorectal cancer. In one meta-analysis study from the journal of the National Cancer Institute, the findings strongly support a relationship between diabetes and increased risk of colon and rectal cancer in both male and female. In the study, hyperinsulinemia or factors related to insulin resistance such as hyperglycemia and hypertriglyceridemia are associated with the development of colorectal cancer. Health professionals should aware this and prepare to avoid any complications from diabetes.

In animal study, it has demonstrated that walnut in diet inhibit colorectal cancer growth by suppressing angiogenesis. Walnut contains several compounds anti-tumorigenic properties such as ellagic acids, selenium and phytosterols. Next is flaxseed oil. Flaxseed is a very rich source of phytoestrogens which may reduce colorectal cancer risk by reducing angiogenesis and metastasis in colon and rectum. However, further study should be done on human.

In a meta-analysis study on the relationship between vitamin D and colorectal cancer, the result shows the evidence to date suggest that daily intake of 1000-2000 IU/day of vitamin D3 could reduce the incidence of colorectal cancer with minimal. There is a controversial on the intake of natural vitamin D when experts say too much sun exposure can cause skin cancer. Where patients can do their activities when experts recommend them to be active? It makes patients confuse with clueless. Go get natural vitamin D from pleasurable morning sun. Do not expose to sun in midday which could be very hot and not fit to your skin.

References:

Charles S. Fuchs et al. (1999). Dietary Fiber And The Risk Of Colorectal Cancer And Adenoma In Women. N Engl J Med 1999; 340:169-176

Edward D. Gorham et al. (2007). Optimal Vitamin D Status for Colorectal Cancer Prevention: A Quantitative Meta Analysis. American Journal of Preventive Medicine, Vol 32, Issue 3, March 2007, Pages 210–216

Jutta M. Nagel et al. Dietary Walnuts Inhibit Colorectal Cancer Growth In Mice By Suppressing Angiogenesis. Nutrition 28 (2012) 67–75

Malaysia Cancer Statistics - Data and Figure Peninsular Malaysia 2006. National Cancer Registry, Ministry of Health Malaysia. 

Susanna C. Larsson et al. (2005). Diabetes Mellitus and Risk of Colorectal Cancer: A Meta-Analysis. Journal of the National Cancer Institute, Vol. 97, No. 22

Van Duijnhoven et al. (2009). Fruit, vegetables, and colorectal cancer risk: the European Prospective Investigation into Cancer and Nutrition. Am J Clin Nutr 2009;89:1441–52.

Yikyung Park et al. (2005). Dietary Fiber Intake and Risk of Colorectal Cancer. December 14, 2005—Vol 294, No. 22