The good news regarding colon cancer is this: It develops slowly—precancerous polyps might take 10 to 15 years to develop into cancer—and early detection can frequently result in a full cure. That implies we have a good chance of preventing it through regular tests and preventive actions. Furthermore, research continues to look into the disease’s probable causes as well as new therapies, including those involving the microbiome and the role the gut may have in its progression.
A cancer diagnosis, regardless of the type, is scary. And the numbers are alarming: Colon cancer, commonly known as colorectal cancer, is the third most prevalent cancer in men and women in the United States, and the second-largest cause of cancer-related mortality. Overall, you have a one-in-twenty chance of contracting the disease in your lifetime. Women are at a somewhat lower risk than males. A number of other inescapable variables, in addition to your sex, have a role in your risk of developing colorectal cancer.
For example, if you have a family history of the illness or a history of colon polyps, inflammatory bowel disease (Crohn’s disease or ulcerative colitis), type 2 diabetes, or some genetic disorders, you’re at a higher risk. Being African-American or older than 50 years increases your chances. Many other risk factors, on the other hand, are controllable, and addressing them can protect you.
Gut Check: The role of the Microbiome
The relationship between colon cancer and the gut microbiome, a term for the billions of microorganisms (bacteria and fungus) that take up home there, is an exciting area of research surrounding possibly modifiable risk factors. Researchers have discovered the presence of numerous types of bacteria in aberrant colon tissue and tumors, and new research has begun to shed light on this connection.
Researchers from the Dana-Farber Cancer Institute and Simon Fraser University in British Columbia separately reported discovering fusobacteria in human colon tumors in 2011. This sparked a drive to further understand the link. However, their findings prompted further questions: do the microorganisms cause cancer directly? Or do the bacteria affect the immunological response of patients or produce substances that promote the development of cancer cells nearby?
Other bacteria, including B.fragilis and a type of E.coli, were discovered in colon cancers earlier this year. The science is a little clearer here: these bacteria, which are widely found in the gut, appear to work together to promote colon cancer growth.
Patients with hereditary risks for colon cancer, such as those with familial adenomatous polyposis, a rare inherited disorder that nearly always leads to the illness, were investigated by researchers from John Hopkins University in Baltimore. Polyps-growths of colon cells that have a mutation or two that might develop cancerous-benign cancer in these people. Sheets of B.fragilis and the suspicious E.coli strain of bacteria had infiltrated the mucous lining of the colon in these subjects, according to the researchers. They came to the conclusion that E.coli produces a toxin that destroys colon cell DNA, whereas B.fragilis damages DNA while also inflaming the tissue. These strains were found in relatively few healthy people’s colon tissue samples. The two bacterial species were also discovered inside the tumors.
In another experiment, researchers gave mice a cancer-causing chemical that causes alterations in colon cell DNA before infecting them with one of these bacteria or the other. What’s the end result? There aren’t many tumors if any at all. When they gave them both kinds, the tumors grew quickly. However, there are still unanswered questions, such as whether bacteria are always or just occasionally responsible for colon cancer in the general population. It’s also too early to apply these findings to cancer prevention directly. Antibiotics, for example, kill germs without discrimination, so using them to target only the types linked to the disease would likely cause more harm than benefit. But I’m hoping that these findings may lead to yet another preventative technique in the future: Doctors may be able to detect these bacteria in the colons of colonoscopy patients; those who process them may require more regular tests. Vaccines against microorganisms may be available in the future for individuals who are at high risk of contracting the disease.
Meanwhile, I see this research as more compelling evidence that you should take good care of your microbiome by practicing stress management, limiting antibiotic use to only when absolutely necessary, embracing probiotics and fermented foods, and following the diet and exercise recommendations below.
“Recent studies have begun to throw light on this relationship, with researchers discovering the presence of many particular kinds of bacteria among aberrant colon tissue and tumors.”
My approach to colon cancer prevention is based on making wise lifestyle changes that address modifiable factors.
- DIET: One of the most powerful weapons we have is nutrition. A healthy diet can also help you maintain your weight—excess body fat, especially abdominal fat, is a risk factor for colon cancer—while also revealing your microbiota.
- Focus on fiber: According to studies, every 10 grams of fiber consumed daily (about equivalent to a cup of beans) reduces the risk of colon cancer by 10%. This might be due to a number of factors: To begin, dietary fiber aids in the movement of material through the digestive system; as fiber consumption increases, waste toxins spend less time in touch with the colon. Low-fiber diets have also been related to chronic inflammation, which is a cause of cancer, as well as an imbalanced microbiota. Fiber, it turns out, feeds the billions of beneficial bacteria that dwell in our intestines, keeping them healthy and happy. Fiber is abundant in fruits, vegetables, legumes, nuts, seeds, and whole grains. In studies, eating a diet rich in fruits and vegetables, particularly spinach, kale, broccoli, and other leafy greens, has been linked to a lower risk of colon cancer; aim for five to nine servings per day.
- Eat very little: if any, red meat. Processed meats, as well as animal proteins like beef, lamb, and pork, are linked to a higher risk of colon cancer (like ham, bacon, hot dogs, and luncheon meat). In fact, eating just 50 grams of processed meats per day, equivalent to a few slices of ham, can increase the risk of colorectal cancer by 18 percent, while consuming 100 grams of red meat per day can increase the risk by 17 percent. Although the specific mechanism by which red and processed meat increases cancer risk is unknown, we do know that a high-processed-food diet leads to a dysbiotic, or imbalanced, microbiome. When feasible, replace this meat with fish, poultry, or whole soy meals.
- Exercise: Colon cancer is one of the most researched diseases in connection to physical exercise, according to the National Cancer Institute. People who improve the frequency, duration, or intensity of their exercises can lower their risk by up to 40%, according to research. Moderate exercise may help you maintain a healthy weight by encouraging regularity. Exercise has also been proven to increase the diversity of microorganisms in the gut, and greater diversity equals better function. On most days of the week, I recommend doing at least 30 minutes of cardiovascular activity (such as brisk walking, jogging, cycling, swimming, or dancing).
- Supplements: Although you should prioritize lifestyle changes like diet and exercise, a few dietary supplements may help reduce your risk of colon cancer. Before including them in your routine, see your doctor.
- Vitamin D: People with greater blood levels of Vitamin D had a lower risk of colon cancer, according to a number of epidemiologic (population) research. However, the findings of research looking into the influence of vitamin D supplementation on the risk of colon cancer have been mixed. For the time being, I recommend that everyone consume 2,000 IU of Vitamin D3 every day.
- Folic acid: Some epidemiological data suggests that there isn’t a clear relationship between folic acid and supplements, and a number of studies have indicated that supplementing increases the risk of non-colorectal malignancies in general. For its preventive benefits, I still advocate supplementing with 400 mcg of folic acid daily but only as part of a B-50 B-complex 30 supplement that contains the complete spectrum of B-vitamins.
- Turmeric: In animal models, this spice and its major component, curcumin, have been shown to be helpful in preventing and treating colon cancer—in fact, their benefits have been compared favorably to those reported for medicines. Curcumin and turmeric, in particular, may help to prevent colon cancer. Turmeric may be added to your diet by eating curry meals in restaurants or at home, or by drinking turmeric tea on a daily basis. To supplement, seek supercritical extracts in doses of 400 to 600 mg in health-food store tablets and capsules, and take them three times daily or as instructed on the package.
EARLY DETECTION is key to winning the colon cancer battle. Once you reach the age of 50, the following tests should be performed routinely. Screenings should be done earlier when there is a family history of colon cancer or polyps. African-Americans may also consider beginning colon cancer screening early, around age 45.
- Fecal occult blood test (to test for blood in the feces) annually if normal.
- A flexible sigmoidoscopy every life years if normal, OR
- A colonoscopy (if normal, every 10 years), OR
- A barium enema every to 5 to 10 years if normal, OR
- A digital rectal exam at the same time the sigmoidoscopy or barium enema is performed (up to 10 percent of tumors can be detected by this low-tech test)