What Is Inflammatory Bowel Disease (IBD)?

Inflammatory bowel disease, or IBD, is an autoimmune disease that affects the gastrointestinal tract and causes inflammatory lesions or ulcers in the intestines. 

Although there is no cure for IBD, the symptoms and inflammation can be managed with medications, diet and lifestyle changes, and, in severe cases, surgeries. 

In this article, learn more about the two forms of IBD, what causes IBD, and ways you can manage it with your diet or lifestyle. 

What Is IBD?

IBD stands for inflammatory bowel disease (not to be confused with irritable bowel syndrome or IBS) and is comprised of two conditions that cause chronic gut inflammation in the digestive system: Crohn’s disease and ulcerative colitis.

Crohn’s disease is often considered the more severe form of IBD, as it causes ulcers or inflammation in any part of the gastrointestinal (GI) tract, from mouth to anus. However, Crohn’s disease most often affects the small intestine and is less common in the upper gastrointestinal tract.

Conversely, ulcerative colitis causes ulcers or inflammation only in the colon (large intestine) and rectum. If the ulcers are only in the rectum, it’s known as ulcerative proctitis. 

Both ulcerative colitis and Crohn’s disease can be mild or severe and are often characterized by diarrhea, rectal bleeding, abdominal pain, fatigue, and weight loss. Most people with IBD have flares and remission (i.e., periods of active illness and symptom flare-ups followed by periods of no or minimal symptoms).

Inflammatory Bowel Disease Symptoms

People with IBD can have mild, moderate, or severe forms of the disease. Common IBD symptoms that occur during flares or the disease onset include:

• Abdominal pain and cramping
• Gas 
• Bloating
• Chronic diarrhea (often bloody diarrhea with mucus)
• Severe fatigue and weakness
• Low appetite
• Weight loss

Inflammatory bowel disease can also cause inflammation in other organs or areas of the body, with some people experiencing: 

• Joint pain
• Skin conditions or inflammatory lesions
• Eye inflammation

Lastly, IBD can lead to severe complications, especially if left untreated, including: 

• Malnutrition
• Bowel obstruction 
• Fistulas and abscesses 
• Anal fissures
• Perforated colon
• Toxic megacolon 
• Severe dehydration from diarrhea

Although IBD itself is not a fatal condition, these complications can be life-threatening. Both Crohn’s disease and ulcerative colitis also increase the risk of colon cancer and colorectal cancer. 

What Causes Inflammatory Bowel Disease?

There is no single cause of ulcerative colitis or Crohn’s disease. Many factors likely play a role in the development of IBD. 

Researchers have identified three factors associated with IBD development: gut dysbiosis, an overactive immune response, and increased intestinal permeability. 

• Dysbiosis: Too many harmful bacteria and too few beneficial bacteria in your gut can lead to IBD because dysbiosis causes inflammation of the mucosal gut lining.¹ 
• Overactive immune system: Inflammatory bowel disease is an autoimmune disease, meaning some part of the immune system (in this case, the gut) is attacking itself. Dysbiosis in the gut can also lead to dysfunction or inappropriate activation of the mucosal immune response, contributing to IBD.¹
• Increased intestinal permeability: Also known as leaky gut, people with IBD are more likely to have increased permeability of the thin mucosal lining of the digestive tract.² This defective mucosal barrier can allow unwanted proteins and molecules to travel from the gut into the bloodstream, triggering an immune response that promotes intestinal inflammation. 

Inflammatory Bowel Disease Risk Factors

Inflammatory bowel disease has many risk factors associated with it, some of which are unchangeable (like age, genetics, and race), while others are modifiable lifestyle-related factors. 

• Genetics: Several gene mutations have been associated with IBD, which increase the chances of developing it.
• Younger age: Most people with IBD are diagnosed before age 30. However, people of all ages can develop IBD.
• Race: IBD is more common in white people than other ethnicities. 
• Family history: If you have a first-degree family member with IBD, you are more likely to develop IBD. 
• Cigarette smoking: Smoking increases the risk of Crohn’s disease but not ulcerative colitis.³ 
• Alcohol use: Alcohol consumption is linked to both the development of IBD and a worsening of symptoms.⁴
• NSAID medication overuse: NSAIDs (non-steroidal anti-inflammatory medications) like ibuprofen or Advil can exacerbate IBD symptoms and contribute to its development.⁵ 
• Antibiotic use: A history of antibiotic use in childhood and younger years increases the risk of IBD, as antibiotics disrupt the gut microbiome.⁶

Ultra-processed foods: One study found that a higher intake of ultra-processed foods (like fast food, most packaged meals, most snack foods, soda, candy, etc.) was associated with a higher incidence of Crohn’s disease but not ulcerative colitis.⁷

IBD Management: Diet and Lifestyle

There are several medications for IBD depending on which form you have and its severity, which you and your healthcare provider will discuss and decide. 

Here, we’ll just be talking about potential ways to manage IBD symptoms with diet, supplements, and lifestyle changes. 

However, not all of these will work for everybody, as IBD is a highly individualized disease. It’s also important to note that you should never stop your IBD medications in favor of a dietary or lifestyle change without speaking to your gastroenterologist. 

Some potential ways to manage IBD symptoms include:

• Stress and mental health management: Through the gut-brain axis, stress is thought to make IBD symptoms worse, as stressful states release hormones that can make the gut even more inflamed.⁸ 
• Supplements: Probiotics, L-glutamine, colostrum, omega-3 fats, vitamin D, and curcumin may help to improve some aspects of IBD, especially inflammation and gut dysbiosis. Specific vitamin and mineral supplements may also be needed to address any deficiencies from suboptimal nutrient absorption in the gut.
• Eliminating problematic trigger foods: Trigger foods will differ for everyone, but common ones include dairy, gluten or wheat, beans, cruciferous vegetables, high-fiber foods, caffeine, alcohol, sugar, artificial sweeteners, and spicy foods.
• Low-residue diet: When in an IBD flare, many people feel relief by following a low-residue (very-low fiber) diet, as fiber can aggravate the inflammatory lesions. 
• Specific Carbohydrate Diet (SCD): A specialized diet that eliminates certain carbohydrates that can be hard to digest in some people with IBD. SCD only allows monosaccharides (like glucose and fructose in fruits, non-starchy vegetables, and honey) but not harder-to-digest, larger carbohydrates in foods like starches, grains, beans, and lactose. 
• Low FODMAP Diet: FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) are sugars in certain foods that the small intestine absorbs poorly. When FODMAP sugars ferment in the gut of someone with IBD, symptoms like gas, bloating, and cramping can occur. FODMAPs are found in high amounts in foods like garlic, onions, tomatoes, apples, wheat, beans, and more. 
• Anti-inflammatory diet: When tolerated, anti-inflammatory foods like berries, leafy greens, herbs, spices, green tea, salmon, yogurt, kefir, and olive oil may help with gut inflammation. 

Inflammatory Bowel Disease FAQs