IBS vs. Colon Cancer: Differences and Similarities

Irritable bowel syndrome (IBS) and colon cancer are conditions that affect the colon, also known as the large intestine. IBS is a group of digestive symptoms that occur when the gut doesn’t function normally due to issues with how your brain and gut interact. Colon cancer occurs when cells in the colon mutate and grow uncontrollably.

IBS and colon cancer can share many similar symptoms. However, the conditions’ prognoses and treatment options are different.

Irritable bowel syndrome (IBS) and colon cancer affect the same area of the body and may cause similar symptoms. As colon cancer grows and spreads, it causes additional symptoms. Colon cancer symptoms will worsen over time, while IBS symptoms can come and go.

While IBS and colon cancer both affect the large intestine, they are very different from one another. Here are some factors that set them apart.

How Common They Are

IBS: It’s one of the most common conditions healthcare providers see. IBS affects about 10-15% of adults in the United States. 

Colon cancer: It is less common than IBS. About 4% of people in the U.S. will be diagnosed with colon cancer.

How They’re Treated

IBS: The goal of IBS treatment is to manage the symptoms and prevent complications. IBS treatment options may include:

• Diet changes: Follow a low-FODMAP diet, increase your fiber intake, and avoid gluten.
• Medications: Take antidiarrheals like Immodium (loperamide), laxatives like Miralax (polyethylene glycol), and antispasmodics like Bentyl (dicyclomine ).
• Probiotics: Eat probiotic-rich foods like yogurt or take a supplement.
• Mental health therapy: Cognitive-behavioral therapy is an effective treatment for IBS.

Colon cancer: The goal of colon cancer treatment is to remove the cancerous tumor and stop its spread. When caught early, colon cancer may be curable. Treatment options for colon cancer vary depending on how advanced the cancer is and may include:

Whether You Can Get Screened for Them

IBS: There is no one test available to screen for IBS. The diagnosis is made based on symptoms and by ruling out other conditions.

Colon cancer: Healthcare providers can perform a colonoscopy to see if you have any cancerous or precancerous growths in your colon. Adults at average risk of colorectal cancer should start regular screenings at age 45. There are also at-home testing options that can help you screen for the cancer.

IBS and colon cancer both affect the large intestine and cause several of the same digestive symptoms. There are other similarities between the two conditions.

The Diagnosis Process

IBS is known as a disease of exclusion, and no test can diagnose IBS. Rather, your healthcare provider may run medical tests to rule out other possible causes, including colon cancer, of your symptoms. Once other conditions have been ruled out, your provider can diagnose IBS. 

To diagnose either condition, your provider will likely perform a thorough physical exam and medical history. They may ask several questions about your symptoms, medical history, and family history. 

Additional tests may include:

• Colonoscopy
• Colon biopsy 
• Blood tests
• Stool tests 
• Ultrasound 
• Computed tomography (CT) scan 

Effects on Mental Health 

Both IBS and colon cancer affect a person’s mental health and overall well-being. About 33% of people with IBS and about 20% of people with colon cancer will experience anxiety or depression. Mental health conditions can negatively affect treatment outcomes. 

Risk Reduction

While it is not possible to completely prevent these conditions, certain lifestyle choices can help reduce the risk.

You can try to prevent or reduce symptoms of IBS by:

• Getting seven to nine hours of sleep each night 
• Engaging in vigorous physical activity
• Avoiding tobacco 
• Eating more fiber to prevent constipation 
• Avoiding gluten (a protein found in wheat)
• Following a low-FODMAP diet 

You can lower your risk of colon cancer by:

• Exercising regularly
• Maintaining a weight that you and your healthcare provider decided is optimal
• Limiting alcohol 
• Avoiding tobacco 
• Reducing your consumption of animal fats
• Eating more fruits, vegetables, and whole grains 

It is possible to have both IBS and colon cancer at the same time. Their causes are different, so you can develop each for separate reasons.

While you can have both, the two conditions are not related. IBS does not damage the colon. People with IBS are not at an increased risk for colon cancer or precancerous colon polyps.

It is common to experience mild abdominal discomfort, constipation, or diarrhea from time to time. If these symptoms don’t improve on their own or come back, consult your primary healthcare provider. Based on your symptoms, they may refer you to a gastroenterologist, a medical doctor who specializes in diagnosing and treating conditions of the digestive tract. 

See your provider right away if you experience:

• Severe abdominal pain
• Dark red or black blood in the stool 
• Persistent vomiting
• Uncontrolled diarrhea 
• Unintended weight loss 

Irritable bowel syndrome (IBS) and colon cancer both affect the large intestine (colon) and may cause similar symptoms, including abdominal pain, diarrhea, and constipation. Colon cancer may also cause rectal bleeding and unintentional weight loss. 

If you develop any possible symptoms of IBS or colon cancer, see a healthcare provider so they can make a diagnosis and get you started on any necessary treatment.