Colon Cancer Prevention
Many people would like to know how they can
prevent cancer. Cancer of the colon, although
easily prevented, is the second leading cause
of cancer-related death in the United States.
In 2013, there were 145,000 cases of colon
cancer diagnosed, and 51,500 people died
from colon cancer that year.
Screening for colorectal cancer can prevent death by detecting and removing polyps before they become cancers. Colon cancer screening for the general population includes colonoscopy starting at age 50 and every ten years after that. If colon polyps are found, colonoscopies are scheduled a little more frequently. Unfortunately, since only about half of all people over 50 get this screening test, only 40% of colon cancers are caught early. It is important to note that tests for blood in the stool, flexible sigmoidoscopy, or rectal exam are not good screening tools for colon cancer, and that colonoscopy remains the 'gold standard.'
Cases of colon cancer are highest in Western countries. There are likely multiple reasons for this. Many studies have shown that greater consumption of meat is linked to higher rates of colon cancer. Barbecuing meat may be partly to blame because of the carcinogens produced from high-heat cooking. Studies done in the United States and Europe have shown that there seems to be a direct correlation between the number of servings of red meat (beef or pork) eaten per week, and the risk for colorectal cancer. Therefore, a reasonable recommendation to prevent colon/rectal cancer would be to limit red meat intake to two or fewer servings per week.
Many studies have shown that increased physical activity decreases the risk for colon cancer. In fact, regular exercise has not only been shown to decrease the risk for developing colon cancer in the first place, but also decreases the risk for relapse of the disease in patients who have a history of colorectal cancer. How much exercise is enough? The more activity the better. The recommendation is for at least 15 MET-hours a week. Walking for one hour equals three METS, running for one hour is 12 METS, and other activities are in between. Simply walking for a total of about five hours a week can significantly decrease the risk for developing colon cancer.
Type II diabetes and obesity also increase the risk of developing colon cancer. Insulin, a hormone made in the pancreas, circulates in the body at high levels in people with diabetes. Insulin stimulates growth of colon cancer cells. In fact, when colon cancer cells are studied in the laboratory, scientists use insulin to cause the cancer cells to grow. Maintaining a healthy body weight (BMI less than 25) and conscientiously managing diabetes can decrease the risk for colon cancer.
No dietary supplements have been proven to decrease the risk for colorectal cancer. However, vitamin D may have a role in preventing colon cancer. Studies have shown that people with higher levels of vitamin D in the blood are less likely to develop colon cancer. It is estimated that vitamin D levels are less than optimal in up to 70% of the population. Ask your doctor about testing for vitamin D levels.
As you can see, there are many simple ways to decrease your risk for cancer. It is estimated that 71% of all colon cancer could be eliminated by adhering to the following guidelines: maintain a BMI of less than 25, get 15 MET-hours of physical activity a week, take a daily multivitamin, consume no more than 15 grams of alcohol a day (the equivalent of one beer or glass of wine), don't smoke and eat two or fewer servings of red meat a week. If you would like more information on this topic, please visit the US Centers for Disease Control website at http://cdc.gov.