Can Coffee Cause Ulcerative Colitis Flare-Ups – or Make Them Worse?

Written by Rachel Reiff Ellis
Medically Reviewed by Melinda Ratini, MS, DO on March 19, 2025
5 min read

Coffee and ulcerative colitis (UC) have a complicated relationship. If you live with UC, you may be wondering if you need to forgo your morning cup of joe to prevent flares. But the answer isn’t straightforward. 

Coffee can irritate your intestines and increase your need to have a bowel movement. But at the same time, studies show coffee has antioxidant and anti-inflammatory properties. Other data suggests it may even protect you from the disease in the first place.

"There’s some evidence that drinking coffee may actually prevent ulcerative colitis, but the evidence isn’t sufficient to recommend coffee drinking to protect against the disease," says Stephen B. Hanauer, MD, medical director of the Digestive Health Center at Northwestern Medicine. 

Although research is still ongoing, there are certain facts about coffee – and the parts that make it up – that are good to know if you live with ulcerative colitis so you can make the best choice for your own digestive health.   

Some research shows coffee doesn’t have a link to UC risk, meaning it’s not a trigger for getting the condition. But can coffee cause flares in people who already have UC? 

Although many studies have looked at how diet affects UC, there aren’t many high-quality or large studies on the direct relationship between coffee and UC flares. 

UC symptoms happen because of the inflammation it causes in your colon. But studies on coffee show that it doesn’t actually kick off the inflammatory process in the gut. In fact, plant-based chemicals called polyphenols in coffee have anti-inflammatory effects. 

But coffee does increase "gut motility," which is a term that refers to the overall process of moving food, liquids, and waste through your digestive system. When you have a gut disorder that’s already increasing your bowel movements, that may be a downside to the drink.  

"As with most things we eat and drink, I typically advocate moderation, particularly for patients who have more bowel movements than they would like,” says Hanauer. 

Caffeine

An 8-ounce cup of brewed coffee has about 95 milligrams of caffeine. The average adult would need to drink four to five times that amount to start having negative effects, according to the FDA. But when you have UC, you may want to be more cautious. 

Caffeine stimulates your digestive tract. This can cause loose stools and diarrhea. Also, caffeine can make you jittery, anxious, and affect your sleep, all of which can increase stress and anxiety. The combination of these things can make your UC symptoms worse. 

Bottom line: Even though caffeine is a "trigger food" for UC symptoms, it doesn’t necessarily cause harm or inflammation to your body. It’s important to remember caffeine is in other foods and drinks, too, such as chocolate and tea. Pay attention to how much you’re consuming in a day and factor that into your decision about drinking coffee.

Acidity

Certain coffee blends – such as those made from Arabica beans and light roast coffee – are more acidic than others. This acid can irritate the lining of your gut, which may already be irritated by your UC, making your symptoms more severe. 

Acids also boost a hormone called gastrin. This tells muscles that line your digestive tract to start moving. This can make you feel UC symptoms more urgently, meaning you feel more rushed to get to the bathroom and relieve yourself.

Coffee's laxative effect

Coffee is a natural laxative. A laxative is a substance that stimulates your bowels or softens your stools. One reason is because of a hormone called cholecystokinin, which plays a key role in your digestive process. This laxative effect can make your diarrhea worse, and cause cramping during a UC flare, after you drink a mug of java. 

When you have UC, you may not be able to tolerate coffee, but you might be able to drink it in moderation without much change in your symptoms. You know your body best. Take note of how your UC symptoms flare – or don’t – after you have coffee. Perhaps try to go coffee-free for a week or so and see if that makes a difference in your condition, then make a decision based on what you observe.

If coffee is still on the table for you, try these tips to make each cup more enjoyable for your gut:

  • Keep your cups of coffee small and infrequent.
  • Stick to low-acid options such as cold brew or dark roast.
  • Skip dairy creamers and try almond, oat, or soy instead. 
  • Avoid artificial sweeteners in your coffee.
  • Stay hydrated to counterbalance coffee’s diuretic effects.
  • Don’t drink coffee on an empty stomach.
  • Use a paper filter instead of a metal filter – paper traps more of the acids, keeping them out of your coffee

Can I drink decaf coffee with ulcerative colitis?

Some people find that a switch to decaf lets them keep enjoying the taste and routine of coffee without as many negative effects on their bowels. 

You might be surprised to learn decaf coffee isn’t completely caffeine-free. An 8-ounce cup of decaf coffee has 4 to 5 milligrams of caffeine. That’s drastically less than a cup of caffeinated coffee. But if you’re sensitive to caffeine’s effects, you may still feel it. 

If you discover that coffee and your UC just don’t mix, try these other options as your morning (or mid-afternoon) pick-me-up instead:

Low-caffeine tea. Try green tea, which is full of antioxidants and other health benefits.

Caffeine-free tea. Rooibos, chamomile, peppermint, and ginger are naturally caffeine-free.

Chicory root coffee. Made from ground roots of a blue-flowered herb that’s part of the dandelion family, you brew this caffeine-free drink just like regular coffee.  

Bone broth. You make bone broth by simmering animal bones (beef, chicken, or pork) in water for an extended period. It’s full of nutrients, and one study found that it may even promote healing in the gut from UC damage.  

Breakfast smoothies. Blend up veggies, fruits, and more to make a tasty drink that will start your day with minerals and vitamins. 

Coffee and ulcerative colitis (UC) have a complex relationship. Coffee’s caffeine and acid can irritate the lining of your gut and trigger symptoms like diarrhea. People with UC tolerate coffee differently, so it's important to monitor your own reaction. Some people with UC find it helpful to stick with low-acid options, or alternatives like decaf coffee, chicory root coffee, or herbal teas.