Is Ulcerative Colitis an Autoimmune Disease?

Medically Reviewed on 8/30/2022
ulcerative colitis (UC)
Ulcerative colitis (UC) is considered to be an autoimmune disease.

Ulcerative colitis (UC) is considered to be an autoimmune disease. With autoimmune disorders, your immune system goes awry and attacks your own body instead of defending itself from infections and illnesses. 

The main abnormality that causes inflammation in ulcerative colitis is an exaggerated T cell response that causes swelling and ulcers in the inner layer of the large intestine. The imbalance between the T cells, a type of white blood cell essential to the immune system, and natural killer cells causes the secretion of many chemicals in the gut that damage the cells in the lining.

What factors contribute to ulcerative colitis?

While the exact cause of UC is unknown, several factors can contribute to the condition.


Inherited genes may cause the development of UC:

  • Family history: Family history of inflammatory bowel disease is the most common risk factor for UC. The risk is particularly high (about 5%-16% percent higher) if first-degree relatives have had the condition.
  • HLA haplotype DRB1*0103: The HLA complex is an area located on chromosome 6 that determines the training and behavior of T cells. In people with the HLA haplotype DRB1*0103, T cells behave abnormally under certain circumstances, synthesizing proinflammatory cytokines (substances causing inflammation) and attacking normal gut cells.

Changes in the gut microbiome

Your gut is home to many types of bacteria that keep your gut healthy. Poor diet and overuse of antibiotics or other drugs can decrease the number of good bacteria and trigger UC. Abnormal interactions between stomach flu bacteria and good gut bacteria can also damage the intestinal cells due to the autoimmune mechanism.


Your gut has its own immune system, which is maintained through a type of white blood cell called IgA. Many doctors believe that improved sanitation in industrialized countries reduces the exposure to gut infections during childhood. If you haven’t been exposed to such infections, your gut immune system isn’t trained enough and the maturation of your gut’s mucosal immune system is restricted. This may cause an attack of UC through an inappropriate immune response to something like the stomach flu.

Environmental factors

Recurrent Salmonella, Shigella, and Campylobacter infections and certain drugs (NSAIDs, birth control pills) can trigger ulcerative colitis. An acute intestinal infection can lead to changes in the gut environment, triggering the start of a chronic inflammatory process in genetically predisposed people.

Can diet help with ulcerative colitis symptoms?

If you’ve been diagnosed with UC, you may find it easier to eat smaller, more frequent meals rather than a few large ones throughout the day. Eating a balanced diet of fresh fruits, steamed vegetables, simple carbs, and nutritional supplements can help you keep your gut healthy.

Foods to eat

Studies have found that the following foods may help ease gut inflammation and reduce UC symptoms:

  • Probiotics found in yogurt, curd, and kefir
  • Linoleic acid found in walnuts, olive oil, egg yolks, and coconut oil may help prevent flare-ups.
  • Good fats like eicosapentaenoic acid (EPA) found in fatty fishes like sea cod and salmon 
  • Lean pork, white meat poultry, soy, eggs, and firm tofu
  • Low-fiber fruits like bananas, cantaloupe, and honeydew melon and cooked fruits
  • Gluten-free or dairy-free products

Foods to avoid

The following foods may be irritating to your gut:

  • Foods high in processed fat
  • Legumes with high fiber content
  • Sulfurous vegetables like broccoli, cauliflower, and raw asparagus
  • Sugars like sorbitol, mannitol found in sugar-free gum, candy, and ice cream
  • Spices like pepper and chilies
  • Alcoholic beverages and caffeinated drinks

Some have found benefits from eating a diet low in FODMAPs, which are highly fermentable carbs found in meats, fruits, dairy, and lots of other foods. 

To better understand what diet is right for you, it’s best to speak to a dietician.


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Medically Reviewed on 8/30/2022
Crohn's & Colitis Foundation. "What Should I Eat?" <>.

Ordás I, Eckmann L, Talamini M, Baumgart DC, Sandborn WJ. "Ulcerative Colitis." The Lancet 380(9853) 2012: 1606-1619. <>.