What Foods Trigger Ulcerative Colitis?

Medically Reviewed on 9/1/2022

How should I begin to find the right diet for my ulcerative colitis?

Ulcerative colitis (or, inflammatory bowel disease) is a difficult condition to live with. Foods that trigger ulcerative colitis include raw green vegetables, lactose, sugar alcohol, caffeine, alcohol, whole grains, and foods high in fat.
Foods that trigger ulcerative colitis include raw green vegetables, lactose, sugar alcohol, caffeine, alcohol, whole grains, and foods high in fat.

Ulcerative colitis (or inflammatory bowel disease) is a difficult condition to live with. Curing it is impossible: You can only hope to manage it to the best of your ability. Doctors advise eating foods that help to calm down your symptoms, so you should pay attention to what you eat and simultaneously avoid "bad" foods that aggravate your ulcerative colitis.

The food you eat is crucial to your nutrition and well-being. People with inflammatory bowel disease are frequently malnourished, and this is because ulcerative colitis often causes the following: 

  • Poor digestion 
  • Limited absorption of proteins, fats, carbohydrates, water, vitamins, and minerals
  • Loss of the urge to eat 
  • Unintentional weight loss 
  • More significant nutritional needs due to the disease

Because of this, you must eat a diet that helps manage your ulcerative colitis and contains many nutrients. No one diet works for everyone that has this condition. The best way to figure out what works for you is by keeping a food journal.

To do this, you should write down what you eat every day. Then, write down all of your symptoms and their severity. From this, you will be able to tell which foods trigger or worsen your ulcerative colitis.

Be sure to never eliminate a whole food group at once, as this can often lead to a lessening of vital nutrients. Additionally, try to only add in types of food one at a time so that you can understand their impact on your body.

Your doctor may also suggest you go on an elimination diet. This is a diet in which you will systematically stop eating certain foods to try and understand which foods trigger your ulcerative colitis. These diets should only be done under medical supervision.

What foods should I avoid if I have ulcerative colitis?

Again, each person who has ulcerative colitis will need to find their personalized diet. However, here are some of the most common types of foods that trigger ulcerative colitis:

Raw Green Vegetables

You should avoid foods that give you more stool. Foods that do this are most often foods with a lot of fiber

Green or cruciferous vegetables contain a large amount of fiber, especially when they are raw. If you have ulcerative colitis, you should try to stick to fully cooked, skinless, and non-cruciferous vegetables. 

Some examples of cruciferous vegetables are:

  • Arugula 
  • Broccoli
  • Cauliflower
  • Cabbage
  • Kale
  • Radishes
  • Collard greens 
  • Bok choy


Lactose is the sugar found in milk and other dairy products. Often, it can exacerbate your ulcerative colitis symptoms through abdominal pain and diarrhea. Not all people react to all dairy products in the same way, though, so be sure to monitor your dairy usage and see which dairy products might affect you in that way.

Sugar Alcohols

Certain sugars are not absorbable by your body. These are sugar alcohols such as sorbitol and mannitol. Often, these are the sugar additives in products such as:

  • Sugar-free gum
  • Candy
  • Ice cream
  • Certain fruits
  • Specific fruit juices

Alcohol and Caffeine

Both alcohol and caffeine can shift anyone’s GI tract, regardless of whether or not they have ulcerative colitis. This is especially true when you are having an ulcerative colitis flare-up. Caffeine specifically can trigger diarrhea.

Whole Grains

Typically, whole grains are a type of food you eat when you need more fiber. If you have ulcerative colitis, the incredible amount of fiber in whole grains can trigger symptoms. Examples of whole wheat include the following:

  • Barley 
  • Brown rice
  • Buckwheat
  • Bulgur
  • Millet
  • Oatmeal 
  • Popcorn 

High-Fat Foods

Eating foods with certain types of fats has been linked with triggering and developing ulcerative colitis. This is due to how an acid called linoleic acid changes during your digestive process. Once it fully changes, it causes inflammation that starts to trigger ulcerative colitis. 

The following foods have these sorts of fats:

  • Red meat
  • Corn oil
  • Sunflower oils
  • Margarine
  • Butter 
  • Cream
  • Fried food
  • Greasy food

What foods often help with ulcerative colitis?

Alternatively, some of the following foods are commonly known to be a part of a diet that works with ulcerative colitis:

  • White bread
  • Refined wheat breakfast cereals
  • White rice
  • Refined pasta and noodles
  • Cooked vegetables 
  • Lean meat and fish 
  • Eggs


Inflammatory Bowel Disease (IBD) Causes, Symptoms, Treatment See Slideshow
Medically Reviewed on 9/1/2022

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National Cancer Institute. "Cruciferous Vegetables and Cancer Prevention."

NHS. "Living with Ulcerative colitis."

UCSF Health. "Nutrition Tips for Inflammatory Bowel Disease."

University Hospitals. "Inflammatory Bowel Disease Diet."