IBS vs IBD: What Are The Key Similarities And Differences?
Reviewed by: HU Medical Review Board | Last reviewed December 2022
Irritable bowel syndrome (IBS) and inflammatory bowel disease (IBD) are 2 gastrointestinal (GI) disorders that affect the digestive system. They are often mistaken for each other because some of the symptoms can be similar. But they are 2 very distinct conditions.1
What is IBS?
IBS is a functional GI disorder. It affects how your bowels work. IBS causes stomach pain along with constipation, diarrhea, or alternating bouts of constipation and diarrhea.1
IBS affects about 10 to 15 percent of people in the United States. It is one of the most frequently diagnosed GI conditions today. While anyone can get IBS, it is more common in women than men.1
What is IBD?
IBD is a complex, lifelong disease that causes inflammation in the GI tract. Crohn’s disease and ulcerative colitis (UC) are 2 types of IBD. IBD symptoms can include:1-3
- Stomach pain and severe cramping
- Bloating
- Constipation and/or diarrhea that lasts several weeks and does not go away
- Blood in your stool or on toilet paper
- Urgent bowel movements
- Nausea and vomiting
- Loss of appetite
- Weight loss
- Fatigue
IBD affects about 1.3 percent of people in the US. That translates to about 3 million Americans. While it is much more rare than IBS, rates have been increasing in recent decades.4
Similarities between IBS and IBD
IBS and IBD have some features in common, such as symptoms and who it affects:1-5
- Both mostly affect people under the age of 50.
- Both may be caused by a bacterial infection in the gut.
- Both may be caused by inflammation in the gut.
- Both may result from changes to the gut environment (microbiome).
- Both have similar symptoms,like bloating, constipation, and diarrhea.
- Both can impact quality of life.
- Both can be treated but not cured.
It is possible to have IBD and IBS at the same time. That being said, if your doctor has ruled out IBD and you are suspected of having IBS, there is no evidence that shows IBS progresses to more serious conditions like Crohn’s disease or ulcerative colitis.5
Differences between IBS and IBD
IBS is a functional GI disorder. This means that it affects the digestive system but does not cause any visible or structural damage to the GI tract.1
IBD, on the other hand, is a chronic inflammatory disease that may change the structure of the intestines and cause damage to the GI tract. These changes can be seen through diagnostic imaging tests, such as CT scans and an outpatient procedure in which a small scope with a camera on the end is used to look inside the GI tract (endoscopy).1,2,5,6
Here are some other key differences between IBS and IBD:1,4,5
- IBS is more common than IBD.
- IBS is found worldwide – despite some variations in location – but IBD is more common in people who are white.
- IBS tends to affect more women than men. IBD affects women and men equally.
- IBD is believed to have a genetic component, whereas genetics is not as clearly documented for IBS.
- IBS is mostly managed by addressing symptoms in a less structured manner with drugs and lifestyle changes, while IBD is managed using a step-wise approach with various drugs.
- IBD can lead to serious complications such as bowel obstruction, malnutrition, infection, and – in severe cases – colon cancer.
Treating IBS and IBD
Treatment for IBS and IBD is multifaceted. It is not one size fits all. For both conditions, treatment typically involves a combination of:5
- Drug therapy
- Diet and nutrition
- Stress management
- Mental health counseling
For people with IBS and IBD, diet can play a role in reducing the severity of symptoms. Certain foods – like fried, fatty foods and dairy – can make symptoms worse. But diet and nutrition are only one piece of the treatment puzzle.5
Here are some other tactics that can help manage IBS and IBD symptoms:5
- Keep a food diary. This can help identify which foods are not well tolerated.
- Stay hydrated. If you have chronic diarrhea (a common symptom of both IBS and IBD), you can quickly become dehydrated. Drink plenty of fluids.
- Eat smaller meals throughout the day. Big meals can lead to bloating and discomfort.
- Reduce stress. Managing stress can lessen symptoms in people with IBS and IBD. Get regular exercise, try meditation, make time for relaxation, and/or speak with a therapist.
- Get plenty of sleep. Sleep helps restore our bodies. Feeling tired will only increase stress. Aim to get 7 to 9 hours of sleep each night.
Getting an accurate diagnosis
Because IBS and IBD require different approaches to treatment, it is essential that you get accurately diagnosed. Speak with your doctor if you are having any symptoms that concern you. They will perform a physical exam and may suggest other diagnostic tests – blood tests, stool tests, and endoscopies – to rule out other issues and conditions.1,5,6
Seek support
If you have IBS or IBD, you do not have to live with painful and debilitating symptoms. Work with a gastroenterologist and a dietitian to develop a treatment plan that is right for you.5
In addition, there are many resources out there for people who live with IBS and IBD, including the Crohn’s and Colitis Foundation and the International Foundation for Gastrointestinal Disorders.5