Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that affects the colon. It’s associated with sores and ulcers throughout the lining of the colon or large intestine.
Symptoms of a UC flare include bloody diarrhea, frequent stools, mucous-like stools, abdominal pain, general feelings of fatigue, and weight loss. During remission, those symptoms reside (
Coffee is known to impact the digestive tract. Yet, research on how this beverage may influence the risk of developing UC and management of its symptoms is still evolving (
This article discusses the relationship between coffee and UC, whether coffee triggers UC flares, and tips for managing potential gut-related side effects from drinking coffee.
Coffee is a popular drink enjoyed worldwide. It’s often considered a part of a healthy diet if consumed in moderation.
A cup of coffee contains caffeine, beneficial antioxidant plant compounds known as polyphenols, and acids like chlorogenic acid (
The drink may increase stomach acid, lead to heartburn, stimulate defecation, and affect the gut microbiome — the colony of microorganisms that reside in your gut (
Some of these effects might explain why research indicates that drinking coffee could protect you from developing UC and why the drink may exacerbate symptoms for someone already living with the condition.
Still, a lot remains unknown about coffee’s impact on UC.
Coffee contains many active compounds, including caffeine and antioxidants, that may influence the drink’s effects on your body and UC.
However, the exact reason behind coffee’s possible UC benefits is not fully understood.
Coffee may have anti-inflammatory properties, and research suggests that an anti-inflammatory diet could help reduce the risk of UC. Plus, coffee is rich in antioxidant polyphenols, which may have similar effects (
Coffee has also been found to positively affect the gut microbiome as it has prebiotic properties. In other words, coffee feeds the good bacteria in your gut and lowers harmful specifics of microbes, thereby supporting a healthy microbiome in the large intestine (
Research suggests that drinking coffee isn’t a risk factor for UC. It may even protect you from developing the condition.
While some people attribute their UC symptoms to certain foods, only a few high quality studies have assessed how your diet may impact the condition. Further, to date, no studies have focused on UC and coffee consumption (
Instead of relying on studies, people with UC often identify which foods and beverages trigger their intestinal problems through trial and error — either on their own or with the help of a healthcare professional like a registered dietitian (
Caffeine and UC symptoms
Caffeine is considered a stimulant drug that boosts energy and alertness.
Coffee can cause contractions within your digestive tract and speed up the elimination of its contents. In fact, one in three people report that drinking coffee increases the desire to defecate as soon as four minutes after consumption (
This effect was once attributed to coffee’s natural caffeine content. However, both decaffeinated and caffeinated coffee has been shown to stimulate bowel movements, so the effect is likely caused by other chemical compounds like polyphenols or acids (
Because diarrhea is a common symptom of UC, anything that increases bowel movements may be undesirable. So, whether or not caffeine is at fault, coffee may be best avoided if you have UC and find that it worsens your symptoms.
Eliminating coffee may improve UC symptoms in some people
While many people with IBD drink coffee, some do avoid it and attribute some of their intestinal symptoms to the drink (
In a 2015 study in 443 people with IBD — both Crohn’s and UC — 73% of the participants consumed coffee regularly. A whopping 96% of the participants who attributed a positive impact of coffee on IBD symptoms regularly enjoyed the drink (
Of those not drinking coffee, 62% believed that the drink worsened intestinal symptoms, though this was more prevalent for those with Crohn’s disease than people with UC. Plus, a negative perception of coffee did not always translate to avoiding it (
In a 2021 survey in 208 people in UC remission, 37% believed diet can initiate symptoms and 24% reported avoiding coffee (
In other words, it appears that some, but not all, people living with UC avoid coffee as they believe it may affect their symptoms. Still, many people with the condition drink coffee with no perceived negative effects (
There is little data on coffee’s role on UC. While it may trigger symptoms in some people, others may tolerate it. Thus, the best way to identify if coffee affects you is to work with a healthcare professional.
Although not ideal, the main approach to IBD symptom management is generally trial and error. This is also the case when learning what you can eat and drink.
The Crohn’s & Colitis Foundation recommends using a food diary to figure out which foods may be your triggers (16).
Depending on what your triggers are, consider these tips to see if they improve your tolerance to coffee.
Try a smaller serving size
Maybe you’re unable to tolerate larger servings of coffee, but sticking to smaller portions can be possible.
If you keep a food diary, also record how much of the food or beverage you consume. You might find your sweet spot at one cup of coffee per day versus three.
Keep in mind that 1 cup of coffee is defined as 8 ounces (236.6 mL) and that the smallest size offered at many coffee shops can be more than this.
Limit excess added sugars and sugar alcohols
Sugary foods are also on the list of potential trigger foods from the Crohn’s & Colitis Foundation (11).
Meanwhile, sugar alcohols like sorbitol and mannitol may be added to sugar-free coffee creamers. Sugar alcohols are also listed as potential UC triggers and may induce diarrhea in some people (11,
Try opting for unsweetened coffee to see if this triggers any UC symptoms. If you like and tolerate milk, milk alternatives, or cream in your drink, choose unsweetened versions of these add-ons.
Choose a dairy-free alternative
Many people with IBD avoid dairy due to adverse symptoms resulting from dairy consumption. If you’re unsure whether the coffee or dairy may aggravate your symptoms, try to trial and error them separately (
There are many plant-based milk and creamer options available — including soy, almond, oat, and coconut — that you can add to your coffee instead.
Avoid sources of carrageenan
Carrageenan is a food additive derived from seaweed. It’s used to thicken and preserve many foods, including some coffee creamers (
In a small 2017 study, 12 people with UC were told to avoid all sources of carrageenan in the diet. Half received a placebo while the other half received carrageenan. Participants were interviewed every 2 weeks and followed for a year or until relapse (
No participants receiving the placebo experienced a relapse, whereas three receiving the carrageenan supplement did (
Although interesting, this is just a small, preliminary study, and it only showed marginal differences in UC outcomes. Ultimately, more research is needed to learn more — especially since carrageenan is not commonly consumed in supplement form.
Keeping a diary of the types and quantities of foods and drinks you consume can help identify potential triggers of your symptoms.
Staying hydrated with water is always important, but especially so if you’re experiencing a UC flare and losing a lot of liquid through frequent, runny stools.
In addition, consider adding electrolyte tablets to water or drinking electrolyte drinks during a severe flare. It’s important to replenish lost electrolytes to stay hydrated and keep your body’s nervous system and muscles working optimally (
However, keep in mind that green, black, and oolong tea all have caffeine. Some herbal varieties can also have a laxative effect on some people. If you react negatively to drinking it, it’s likely best to avoid it (
Try to stay hydrated with water or tea, if tolerated. This is especially important during a flare-up to counteract water losses from diarrhea or runny stools.
A lot is still unknown about the role of diet on UC.
This can be frustrating since it means that there’s no clear-cut answer for which foods may cause a UC flare in those with UC.
Currently, coffee is flagged by professionals as a drink you may need to avoid during a flare. Further, it’s speculated that it may trigger unwanted gut symptoms in some people. Yet, to date, minimal data supports or refutes this stance.
Managing UC is an individualized approach. Lean on your gastroenterologist or seek out a registered dietitian specializing in digestive conditions for additional support and guidance.
If you do find that coffee triggers or worsens your UC symptoms, there are many coffee alternatives to enjoy instead.