How does chronic inflammation cause colorectal cancer?

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Chronic inflammation in the body is common due to certain diets, lack of exercise, obesity and stress. It fuels cancer growth and is a risk factor for colorectal cancer. Find out how to reduce chronic inflammation.


By Nicole Carreau, MD, Colorectal Cancer Medical Oncologist, Norwalk Hospital, part of Nuvance Health


The link between inflammation and cancer is complex but important for everyone to understand. Many Americans are in a constant state of inflammation due to our diets, lack of exercise, alcohol use, smoking and stress. These lifestyle habits are sometimes difficult to manage, given our demanding schedules leaving little time to exercise and decompress, and with varying access to healthy foods,


Research shows a link between chronic inflammation and various cancers, including colorectal cancer. It is no surprise that Inflammatory Bowel Disease (IBD), which includes Crohn’s disease and ulcerative colitis, is a risk factor for colorectal cancer.


Find out why chronic inflammation increases colorectal cancer risk and get tips for reducing inflammation in your body.



What causes inflammation in the body?


Inflammation is the body’s natural response to protect itself against harm, including infections, injuries and toxins. There are two main types of inflammation: acute and chronic.


Acute inflammation is the body’s immediate response to an injury or infection. Signs of acute inflammation are redness, warmth, swelling and pain. Acute inflammation helps the body heal from an injury or infection, such as a broken bone or the flu.


Chronic inflammation, on the other hand, is a prolonged inflammatory response that can last for months or years. Chronic inflammation can damage tissues and organs and is a risk factor for cancer.



What is the link between chronic inflammation and cancer?


Research shows a strong link between chronic inflammation and various forms of cancer. Let’s get into science for a moment! DNA carries your body’s genetic makeup and lives in the nucleus of cells. Cancer happens when changes to DNA cause cells in the body to grow out of control. The uncontrolled cells can form tumors (solid masses). Uncontrolled cells can also damage blood cells, resulting in cancers like leukemia.


OK, so what does this have to do with inflammation in the body? Chronic inflammation contributes to DNA damage, promotes the growth of tumors and suppresses the immune system, creating an environment conducive to cancer development. Therefore, chronic inflammation can fuel cancer growth.


What is colorectal cancer?


Colorectal cancer is the second most common cause of cancer deaths among men and women, according to the American Cancer Society. Colorectal cancer is a broad term for colon cancer and rectal cancer. Both cancers form when cells grow out of control in the part of the digestive tract called the large intestine. Early-stage colorectal cancer stays contained to the large intestine. Advanced-stage colorectal cancer spreads to other parts of the body.


Colorectal cancer is preventable! A gastroenterologist can remove precancerous polyps during a colonoscopy screening before they have a chance to turn into cancer. Colonoscopy screenings can also detect cancer early, when it is easier to treat.



Colorectal cancer rates have declined in people aged 50 and older thanks to colonoscopy screenings. The United States Preventive Services Task Forces (USPSTF) recommends screenings for people at average risk starting at age 45.


But colorectal cancer rates in people younger than 50 are on the rise. If you are not at the screening age yet, it is important to understand your colorectal cancer risk and manage it, including avoiding chronic inflammation.



Does chronic inflammation increase colorectal cancer risk?


Chronic inflammation is a recognized risk factor for colorectal cancer. Conditions characterized by chronic inflammation of the colon, such as Crohn’s disease and ulcerative colitis, have been directly linked to an increased risk of developing colorectal cancer. Studies have shown that individuals with these inflammatory bowel diseases are at a higher risk of colorectal cancer than those without these conditions. This is attributed to the constant cycle of inflammation and healing in the colon, which can lead to mutations in the DNA of the cells lining the colon.



Does reducing chronic inflammation lower colorectal cancer risk?


The good news is, yes — reducing chronic inflammation in the body can lower the risk of developing colorectal cancer. Here are some top ways to achieve this:


Eat a healthy diet: Incorporating anti-inflammatory foods into your diet is a great way to combat chronic inflammation. Focus on a diet rich in fruits, vegetables, whole grains and lean proteins. Foods high in antioxidants, such as berries, nuts and green leafy vegetables, can help reduce inflammation. Additionally, omega-3 fatty acids, found in fatty fish like salmon, have been shown to have anti-inflammatory properties.


Avoid processed foods high in added sugars and unhealthy fats, including saturated and trans fats. Also, avoid high-salt diets since salt also triggers inflammation. Processed foods include packaged snacks, baked goods, deli meats, candy and sweetened beverages.


Moderation is key because it’s nearly impossible to eliminate all processed foods entirely. If you love a ham sandwich or a hot dog at a BBQ, it is to splurge and enjoy one from time to time. But eating these types of foods daily can take a toll on your health.



Exercise regularly: Regular physical activity helps reduce inflammation and improves your overall health. Exercise boosts your immune system, helps you maintain a healthy weight and can even relieve stress — it is a win, win, win to combat inflammation! The American Cancer Society recommends adults get 30 to 60 minutes of moderate exercise most days of the week, or 10 to 20 minutes of intense exercise most days a week.



Avoid alcohol and smoking: Both smoking and excessive alcohol consumption are known to increase inflammation in the body. Quitting smoking and limiting alcohol intake can significantly reduce inflammation and lower your risk of developing colorectal cancer. The U.S. Centers for Disease Control and Prevention (CDC) guidelines define moderate as two drinks or less in a day for men and one drink or less in a day for women.


Get enough sleep: Sleep plays a vital role in reducing inflammation. Your body repairs itself when you sleep. The CDC recommends adults get seven to eight hours of sleep each night.


Manage stress: Research suggests stress activates an inflammatory response in the brain, and chronic stress can lead to increased inflammation in the body. Incorporating stress-reduction techniques such as deep breathing exercises or meditation can help lower stress levels and, consequently, inflammation. You can also relieve stress by doing something you enjoy, whether talking with a friend, playing with your dog or taking a vacation.



Manage your digestive health: If you have or think you have IBD, find a gastroenterologist near you who can help manage your symptoms. Crohn’s disease and ulcerative colitis are inflammatory conditions that increase the risk for colorectal cancer. Your doctor might also monitor you more closely and help manage your risk.



How can you prevent colorectal cancer?


Managing chronic inflammation is one way to lower your risk of colorectal cancer. A healthy diet, regular exercise, limited alcohol consumption, and abstaining from smoking are some of the ways you can take control of the inflammation in your body.



If you are 45 or older, you can also prevent colorectal cancer by having routine colonoscopy screenings. 


Ready for a colonoscopy screening? Find a gastroenterologist near you.


Your doctor may recommend screenings before you are 45 if a first-degree relative (parent, sibling) had a precancerous polyp or cancer. For example, if your mom had a precancerous polyp removed when she was 44, your doctor may recommend you start screenings at age 34. Discuss any family history of colorectal cancer with your primary care physician to find out if you should start screenings early.



The bottom line: You can lower your risk of developing colorectal cancer by understanding the critical role chronic inflammation plays in colorectal cancer and taking steps to reduce it. Embracing a healthy lifestyle not only combats chronic inflammation but also enhances your overall quality of life.