Irritable bowel syndrome, or IBS, is very common. In fact, it’s the most common disease diagnosed by gastroenterologists. It’s estimated that 10 to 15% of adults in the US have IBS, although only about half of those have received an official diagnosis.
If you have this condition, what irritable bowel syndrome signs might you notice? How do you develop IBS? How can IBS be diagnosed?
What is IBS disease?
Irritable bowel syndrome, or IBS, is a condition that affects the digestive tract. People with this condition may experience a variety of digestive symptoms. Although the condition is not life-threatening and is not associated with an increased risk of cancer, it can significantly affect the quality of life and cause disruptions to people’s lives. In fact, people with IBS are three times more likely to miss work than those without IBS. Over time, people with chronic IBS symptoms may be more likely to suffer from conditions like hemorrhoids.
Irritable bowel syndrome symptoms
People with IBS may notice a variety of symptoms, including:
- Excessive gas
- Abdominal pain
- Cramps in the abdomen
- Diarrhea, constipation, or both
These symptoms tend to come and go. Many people notice that there are certain triggers that tend to make their symptoms worse. Certain foods may trigger a person’s IBS, such as wheat, dairy products, beans, certain fruits or vegetables, or carbonated drinks. In addition, many people with IBS notice that their symptoms are worse when they’re feeling stressed.
If you have IBS, you may want to consider keeping a food diary, in which you log what you eat as well as what symptoms you’re having. This can help you to identify any food triggers.
What causes irritable bowel syndrome?
Currently, no one knows what causes IBS. Researchers are working to discover what causes this common condition. However, it’s known that IBS is a functional disorder, meaning that it’s related to how the intestines work. The structure of the tissues of the digestive tract is not changed by IBS, and it doesn’t increase the risk of other conditions like cancer.
It’s believed that IBS mainly involves the function of the muscles and nerves in the digestive tract. The muscles may contract too strongly, which leads to cramps, or too weakly, which leads to constipation. The nervous system triggers muscle contractions in the digestive tract, so changes in nervous system function can also change how the muscles of the digestive system contract. This explains why psychological factors like stress can affect the symptoms of IBS.
The colon is filled with bacteria, which perform a number of useful functions, including helping to break down waste and synthesizing certain vitamins. Researchers have found that people with IBS may have differences in the balance of bacteria that are found in the colon. It’s unclear whether this is a cause of IBS symptoms, but it’s possible.
Irritable bowel syndrome risk factors
There are a few risk factors that make a person more likely to develop IBS. These include:
- Age. People younger than 45 are much more likely to experience IBS than those who are older.
- Gender. Females are twice as likely as males to experience IBS.
- Family history. People with family members who have IBS are more likely to develop it themselves. It’s unclear whether this is due to genetics, environmental factors, or both.
- Mental health. People with a history of trauma, such as experiencing sexual or physical abuse, are more likely to develop IBS. People with anxiety or depression are also more likely to develop this condition.
How do you diagnose irritable bowel syndrome?
There is no specific test for IBS. The process of diagnosis involves first ruling out more serious conditions that can cause similar symptoms, such as colorectal cancer, inflammatory bowel diseases (like ulcerative colitis), diverticulitis, or celiac disease.
This sometimes involves doing a CT scan of the abdomen to check for abnormalities. A colonoscopy may also be needed. In a colonoscopy, a doctor uses a camera on the end of a long flexible tube, which is inserted through the rectum to look inside the colon. Blood tests might also be used, to check for signs of anemia (low red blood cell count), infection, and other abnormalities.
One major red flag is having blood in the stool. Although IBS can cause excessive gas or mucus in a person’s stools, it isn’t generally associated with blood. If there’s evidence of blood in the stool, then this indicates a different diagnosis. For the most convenience and privacy, you can order a home test for blood in the stool. You get a kit sent to your home, provide a stool sample, and send it back to the lab for testing. If there is blood in your stool, then you may have a serious colon disease, and should see your doctor to discuss next steps.
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