Colon Cancer And IBS: What You Need To Know

IBS affects between 3-20% of Americans and is more common in women than in men. Most people with IBS experience mild symptoms. For others, however, the symptoms can be severe to the point of affecting normal daily functions.

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What is irritable bowel syndrome (IBS)?

IBS is a disorder of the large intestines. The condition is also known as spastic colitis, irritable colon, or mucous colitis.

People with IBS often experience several intestinal symptoms that occur together. They may be mild or severe and differ in duration. In worst-case scenarios, IBS can cause permanent damage to the intestines, but this is rare.  

Causes of IBS

We don’t really know what causes IBS, but experts believe it may be caused by a series of abnormal gastrointestinal bowel movements, severe viral or bacterial infections, or a lack of clear communication between the brain and the intestines.

Imbalances in gut microbes¹ may also lead to IBS when sometimes the population of beneficial fungi, bacteria, or viruses in the gut decreases.

Other experts believe that early life stressors may also lead to IBS, especially those experienced during childhood. 


The common symptoms² include, but are not limited to:

  • Diarrhea

  • Bloating and passing of gas

  • Abdominal pain

  • Constipation

  • Cramping

IBS is more common in females than in males, according to research³.

Symptoms in women

Many women who experience symptoms of IBS get them around their time of menstruation. Others experience an increase in the severity of their IBS symptoms during this time. The symptoms are fewer in menopausal women than in menstruating women.

Symptoms in men

The symptoms of IBS in men are quite subdued. Men rarely seek medical attention for this condition.

What is IBS pain like?

Most people experience cramping-like symptoms. They may experience sharp pain with some form of relief after their bowel movements. Others notice significant changes in how often they have bowel movements.

Experiencing episodes of constipation and diarrhea is not uncommon for people suffering from IBS. While the symptoms may come and go away for some people, for others, they remain consistent.

Risk factors of IBS

  • Food: Certain people have reported experiencing increased IBS symptoms after consuming certain foods or beverages.

  • Age: IBS is more prevalent in older people than in younger people.

  • Gender: IBS is more common in women than in men in the United States.

  • A family history of IBS also increases the risk of getting IBS.

  • Feelings of anxiety, depression, and other mental conditions may increase the chances of developing IBS. 

How is IBS diagnosed and treated?

There is no specific diagnostic test for IBS. Your doctor will likely take some time to learn about your medical history, carry out some tests, and perform a physical examination to rule out related conditions such as celiac disease.

Once the physician has ruled out all other conditions, they will likely use the following diagnostic criteria for IBS⁴:

1. Rome criteria:  This involves evaluating a patient for severe abdominal pain that is experienced at least once a week for three months. This pain may be felt during bowel movements, and the frequency of defecation is affected.

2. Type of IBS: IBS can be divided into mixed, diarrhea-predominant, or constipation-predominant.

Your doctor will also ask you about other symptoms that may indicate more serious health conditions, such as anal bleeding and vomiting.


The main aim of treatment is to reduce the symptoms so that you can return to living life normally. For mild symptoms, you will be advised to avoid stressors and watch your diet⁵. Your doctor may ask you to:

  • Stay away from trigger foods.

  • Consume high-fiber foods. Take soluble fiber rather than insoluble fiber. Soluble fiber can be found in apples, carrots, citrus fruits, beans, and peas.

  • Take plenty of fluids.

  • Exercise more

  • Get enough sleep

  • Avoid gassy foods if you suffer from bloating

  • Avoid gluten-rich foods such as barley and wheat

According to experts from the Mayo Clinic⁶,  you can use the following medications for moderate to severe symptoms:

  • Laxatives such as MiraLAX if constipation is a symptom

  • Antidiarrheal medications if loose stools are a symptom

  • Antidepressants if indicated

  • Fiber supplements

  • Pain medications

Medications specific to people suffering from IBS are Eluxadoline, Alosetron, Linactotide, Rifaximin, and Lubiprostone.

If the prescribed treatments fail to work, you may need to be booked for further tests.


Chronic diarrhea and constipation may lead to hemorrhoids (piles). People suffering from IBS also often lead a low quality of life and are likely to be absent from work more often than usual. Suffering from IBS also leads to cases of anxiety and depression, which further complicate the condition.

Does having IBS increase a person's risk of colon cancer?

Although IBS and colon cancer target the same part of the body and have similar symptoms, having irritable bowel syndrome does not increase your risk of getting colon cancer. IBS does not lead to inflammation, which is a primary factor that can cause cancer.

According to a 2010 study⁷, when undergoing a colonoscopy, persons suffering from IBS did not have a higher chance of experiencing colon abnormalities, just as is the case in healthy people.

What percentage of people with IBS end up developing colon cancer?

As mentioned, there is no known correlation between IBS and colon cancer. However, other factors such as age may play a role.

It is also important to note that conditions such as inflammatory bowel disease, which is different from IBS, increase the chances of collateral cancer owing to ongoing inflammation of the large intestine.

IBS vs. colon cancer

While cancer and IBS have many similar symptoms, they also exhibit significant differences.


  • Pain during defecation

  • Significant changes in bowel movements lasting for days

  • Diarrhea

  • Constipation

  • Bloating


People suffering from IBS will notice some white-like mucus in their stool. This is not a symptom of colon cancer. If you have colorectal cancer, you will experience unique symptoms such as:

  • Blood in stool

  • Dark stool

  • General lethargy

  • Bleeding from the rectum

  • Thin, pencil-shaped stools

  • Unexplained weight loss 

Should people with IBS be screened for colon cancer?

The American Cancer Society⁸ advises people to seek medical advice if they have any concerns about abdominal pain or notice major changes in their bowel movements. The symptoms of IBS can also be an indication of other serious underlying conditions such as colon cancer.

The fact that suffering from IBS does not make you more prone to developing colon cancer does not mean that you should take things lightly. You should always take precautions. Inform your doctor of any new symptoms you experience. Do not brush anything off.

Discuss getting screened for colon cancer with your doctor. For the vast majority of people, colonoscopy screening begins at the age of 50.

Most symptoms of colon cancer appear after the disease has spread to other parts of the body, and it may be hard to contain it at advanced stages. Regular screening helps detect and remove precancerous polyps before they have the chance to cause irreversible damage.

Earlier screening may be recommended if there is a family history of colon cancer or if you have other risk factors. Screening is done once every five years.

When to see a doctor if you are concerned about developing colon cancer

Make sure to see a doctor if you develop serious symptoms such as:

  • Severe diarrhea at night

  • Rectal bleeding

  • Anemia caused by a lack of sufficient iron

  • Trouble swallowing

  • Unexplained vomiting

  • Persistent pain that is still prevalent after passing gas or after bowel movements

The lowdown

Given that IBS is a chronic condition, the symptoms will recur from time to time. There is no known cure for the condition, but it can be managed. The best way to manage IBS is to avoid triggers and develop a good relationship with your care provider.

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