Preventing Colorectal Cancer

How a single screening test can save your life.

Preventing Colorectal Cancer

No routine cancer-screening test brings about more anxiety then a colonoscopy. Not necessarily the worry of results either. It's the test itself that drives people to skip the test. It is invasive, uncomfortable, embarrassing and intimate. It is terribly inconvenient: It takes a day to prepare and a day for the test.

Oh yeah. One more thing. It saves lives.

Colorectal cancer is the third most common cancer and the second leading cause of cancer deaths in the US. It is one of the few cancers you can detect early, but also prevent entirely by catching precancerous polyps before they transform into cancer. Colonoscopy, a technique that visualizes the entire length of the colon and rectum, is the gold standard for colon cancer detection.

About Colonoscopy


The colonoscope is the instrument a doctor (usually a gastroenterologist) or technician will use to view the inside of the colon and rectum. It is a long flexible tube that has a lighted tip and a camera and when it is inserted into the rectum it magnifies the folds and curves of the colon onto a TV screen. When something looks suspicious it can be sampled for testing. Precancerous colorectal polyps - stalks of tissue that grow from cells in the colon's lining - can be snipped off at its neck right then and there.

In order for the colon to be viewed unobstructed by stool, patients prepare in advance. This bowel prep procedure is the part of the process that often makes people uneasy. The preferred method varies widely from physician to physician but the idea is the same; clean the colon clear so that no polyp or cancer is missed. An inadequately cleansed colon can jeopardize the effectiveness of the test.

The best way to clear the colon is to forgo solid food entirely (liquids only) and induce diarrhea to expel what solids are left inside the colon. There are a few methods for bowel cleansing; drinking a copious amount of a salty solution, or pills and water - both cause high-volume diarrhea in a few hours. Your doctor will give you specific instructions so read them carefully a few days in advance. Expect to spend the day near the toilet.

During the procedure you will be sedated, not entirely but in enough of a fog to not care. Bring something to do while you wait, listen to music or practice progressive muscle relaxation. Expect to be there a few hours and arrange for someone understanding to pick you up.

Colonoscopy Survival Guide

  • Read instructions from your doctor carefully a few days in advance
  • Get all prep materials ready a day before -- buy some tasty clear liquids, pops, broths and tea
  • Have lemon wedges on hand to help tolerate the salty bowel prep solution
  • Buy soothing disposable wet wipes and skin creams to protect the anus on hand
  • Make sure family members know that you will need the bathroom at a moments notice
  • If you are prone to constipation try using a gentle laxative and herbal tea for a few days before the actual colon cleansing
  • Exercise to keep things moving
  • Stay hydrated

Tips for Colorectal Cancer Prevention


In addition to routine colonoscopy you can help prevent colorectal cancer by avoiding factors that increase your risk and adopting lifestyle that promotes colon health.


Screening colonoscopy is recommended for everyone beginning at age 50 (age 45 and older for African Americans) and every 10 years thereafter if all is clear. If you have a single first-degree relative (parent or sibling) diagnosed with colorectal cancer or polyps you may be at a slightly increased risk that may warrant starting colorectal cancer screening at age 40.

There are alternatives to colonoscopy but they are less likely to prevent cancer compared with the invasive tests: guaiac-based fecal occult blood testing (gFOBT), fecal immunochemical testing (FIT) and stool DNA testing (sDNA), barium enema and computed tomography (CT) colonography. Still, most doctors will recommend colonoscopy to screen for colorectal cancer. [A sigmoidoscopy is a similar tool but only visualizes the first third of the colon.]

Here are more ways to keep your colon healthy.

  • Eliminate red and processed meats or become a vegetarian
  • Eat 9 fistfuls of fruits and vegetables a day and include blueberries, which may contain a colon protective chemical
  • Eat a diet rich in whole grains and high in fiber
  • Reduce or eliminate alcohol
  • Take a daily aspirin (review with physician first)
  • Exercise at least 30 minutes on most days
  • Maintain a healthy weight
  • Take vitamin D and folic acid
  • Maintain health cholesterol profile
  • Eat probiotics -- yogurt miso and other fermented soy products -- foods that contain live bacterial cultures that protect the gut flora

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