- IBS and Crohn's disease both affect the digestive system but have different causes and symptoms.
- IBS is a functional disorder characterized by abdominal pain, bloating, and changes in bowel movements, while Crohn's disease is an autoimmune disorder that can cause inflammation in any part of the digestive tract.
- Accurate diagnosis and proper treatment are crucial for managing the symptoms of both conditions, so it's important to consult a doctor if you suspect you may have either IBS or Crohn's disease.
Irritable bowel syndrome (IBS) and Crohn's disease may share some of the same symptoms, but they are two very different health conditions. Crohn's disease is one of two conditions under inflammatory bowel disease (IBD), a potentially serious condition that impacts the structure of the bowel.
In contrast, IBS is classified as a functional gastrointestinal disorder, meaning there are changes in the function of the GI tract that cause symptoms, but you won't see structural changes or abnormalities on a blood test.
Anytime you notice changes in your digestive health, visiting a healthcare provider is essential. Both IBS and Crohn's disease impact the gut, but the diagnosis and treatment of each condition vary.
Understanding the key differences between IBS and Crohn's disease can help you get the proper support and care for your needs.
IBS vs Crohn's Disease
At first glance, it may be hard to differentiate IBS from Crohn's disease. Aside from both being gastrointestinal disorders, they can share many of the same symptoms. Both conditions can also significantly impact your quality of life.
The most noticeable difference between the two disorders is that while IBS is a functional disorder, Crohn's disease is a chronic inflammatory disease related to autoimmunity. An autoimmune disease means the immune system mistakes healthy tissue for a foreign invader, so immune cells attack tissues and can cause long-term damage.
Having IBS doesn't mean you'll develop Crohn's or vice versa—they are two separate disorders. Let's take a closer look at each in more detail.
What Is Crohn's Disease?
Crohn's disease is a chronic condition that causes inflammation along the GI tract anywhere from the mouth to the anus. The exact cause isn't known, but it's likely a combination of genetics, immune dysfunction, and environmental exposures.
People with Crohn's may experience episodes of remission and relapse, with cases ranging from mild to severe. Over time inflammation in the bowel wall can cause fistulas, bowel obstructions, strictures, and eventually surgery.
Symptoms of Crohn's Disease
Symptoms of Crohn's disease can include:
- Abdominal pain, especially in the right lower belly.
- Weight loss.
- Bleeding or mucus in stools.
- Gas and bloating.
Crohn's disease can also include extraintestinal symptoms, which occur outside of the digestive system. These include eye inflammation, swelling and sores in the mouth, and arthritis (painful, swollen joints).
Diagnosis and Treatment of Crohn's Disease
If you have symptoms of IBD or Crohn's, your doctor will likely recommend a comprehensive work-up, including blood tests, stool tests, endoscopy, and colonoscopy, to confirm and examine any structural changes or inflammation in the intestines.
Fecal calprotectin, a test specifically used for IBD, and inflammatory markers like C-reactive protein (CRP) or Erythrocyte sedimentation rate (ESR) are often used to differentiate between IBS and Crohn's and monitor disease activity.
Treatment for Crohn's depends on the severity and progression of the disease but will usually include a combination of medications, including steroids or biologics to suppress the immune system, plus lifestyle changes.
Diet is essential to support the health of the digestive tract and address inflammation. Certain foods or textures can trigger symptoms or irritate the lining of the intestines, especially during a flare. Undernutrition is a concern for people with Crohn's.
Nourish offers one-on-one counseling for people with Crohn's and accepts the most popular insurance carriers. If you need support, consider booking a virtual appointment with a registered dietitian.
What is IBS?
Irritable bowel syndrome is considered a gut-brain disorder because the brain and nervous system can affect the health and function of the digestive tract.
While not as severe as Crohn's disease in terms of inflammation, IBS can still cause considerable discomfort. It's also extremely common, affecting 5 to 10% of the population worldwide.
There are four categories of IBS, according to the American College of Gastroenterology (ACG):
- IBS-C: Constipation predominant.
- IBS-D: Diarrhea predominant.
- IBS-M: Alternating constipation and diarrhea.
- IBS-U: Meets the criteria for IBS, but stool consistency (loose or hard) doesn’t fall into the expected pattern of the categories.
Women are more likely to be diagnosed with IBS. Prevalence also appears to decrease with age, with 25% fewer people diagnosed after age 50. There's no single cause of IBS, but likely related to factors such as alterations in gut motility, brain-gut interactions, stress, history of food poisoning, and genetic predisposition.
IBS may have a relationship to alterations in the gut immune system, meaning it involves the immune cells and causes inflammation, but it's not an autoimmune process that causes tissue damage, as seen with Crohn's. It often appears with other health conditions, especially anxiety and depression.
Symptoms of IBS
Symptoms of IBS vary from mild to severe and can include:
- Abdominal pain.
- Constipation, diarrhea, or both.
- Bloating and gas.
- Changes in appetite.
Diagnosis and Treatment of IBS
Diagnosis for IBS includes reviewing medical history and an exam to check for underlying conditions like IBD or celiac disease.
The Rome IV criteria, a set of criteria that people with IBS must meet for diagnosis, state that people with IBS should report recurrent abdominal pain at least once a week in the last three months associated with at least 2 of the following:
- Pain related to bowel movements.
- Change in frequency of stool.
- Change in stool form (appearance) of stool.
Like Crohn's, treatment for IBS depends on severity. Lifestyle changes addressing diet, sleep, and stress are often enough to manage IBS symptoms. Medications may help with severe symptoms, but immunosuppressants aren't necessary.
Diet can play a significant role in addressing and managing IBS. Studies suggest that working with a registered dietitian to assess for gaps in nutrition and develop and guide people with IBS through elimination diets can significantly help with quality of life and lowering symptoms.
One of the most common patterns used for IBS is the low FODMAP diet. FODMAP stands for fermentable oligo-, di-, mono-saccharides, and polyols, short-chain carbohydrates found in many foods. Some people find these carbohydrates difficult to digest, causing gas, bloating, and other symptoms.
The low FODMAP is not meant to be a long-term diet because it can be overly restrictive. Working with a dietitian can help you customize the elimination and reintroduction phases to meet your needs.
8 Questions to Help Identify If You Have Crohn's Disease or IBS
You can use the following questions to identify patterns and guide your conversation with your doctor. These results are only a starting point and not a replacement for medical advice.
Consider the following questions:
- Have you experienced ongoing abdominal pain and discomfort at least once a week over the past three months?
- Do you alternate between constipation and diarrhea?
- Do your symptoms improve after having a bowel movement?
- Do you experience anxiety or depression?
- Are you prone to developing mouth sores or ulcers?
- Do you experience fatigue or weakness?
- Do you have unexpected weight loss?
- Do you experience rectal bleeding or blood in your stools?
Interpreting Your Results
If you answered "yes" to questions one through four, IBS could be a possibility to discuss with your doctor.
If you answered yes to any questions on the list, especially numbers four through eight, it's crucial to make an appointment with your doctor as soon as possible to rule out Crohn's disease.
IBS and Crohn's Disease share many of the same symptoms at first glance, but diagnosis and treatment are very different. If any of the questions above resonate with you, or if you notice any changes in bowel habits, especially if accompanied by weight loss or blood in your stool, make sure you reach out to your care provider immediately.
Managing Gut Health with an RD
An IBS registered dietitian is an essential part of your care team for any digestive condition. Diet can significantly impact symptom management so you can feel better and get your life back. Connect with an RD today.
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