Does coffee help in stopping diarrhea? What the science says about caffeine and gut health

October 15, 2025 •

4 min read

While some people experience a boost in bowel regularity from their morning cup, medical experts consistently advise against consuming coffee during a bout of diarrhea. Contrary to any assumption that it might help, coffee does not help in stopping diarrhea and can often exacerbate the condition.

Quick Summary

Coffee does not stop diarrhea and often makes it worse due to its laxative effects. The beverage's caffeine, acidity, and other compounds stimulate gut motility and hormone release, which can lead to faster transit time and looser stools. Avoiding coffee and focusing on hydration and bland foods is a better strategy for relief.

Key Points

Laxative Effect: Coffee, both caffeinated and decaffeinated, has a laxative effect that increases gut motility and bowel movements, making it unsuitable for treating diarrhea.
Hormonal Stimulation: Coffee triggers the release of digestive hormones like gastrin and CCK, which can accelerate the digestive process and worsen diarrhea symptoms.
Dehydration Risk: Caffeine is a diuretic that increases fluid loss, which is dangerous during diarrhea when the body is already losing significant water and electrolytes.
Irritating Acidity: The acidic compounds in coffee can irritate the stomach lining, contributing to digestive distress and exacerbating diarrhea.
Avoid Additives: Dairy or artificial sweeteners added to coffee can also worsen diarrhea, especially for those who are lactose intolerant or sensitive to sugar alcohols.
Focus on Hydration: The primary treatment for diarrhea is rehydration with water, broth, and electrolyte solutions, all of which are the opposite of coffee's diuretic effect.

The Surprising Truth About Coffee and Diarrhea

For many, a cup of coffee is a daily ritual and a perceived aid for sluggish digestion. So, the question of whether coffee can help with diarrhea, or at least not make it worse, is a common one. The surprising and clear answer from medical and nutritional experts is that coffee, particularly the caffeinated variety, is contraindicated when experiencing diarrhea. Instead of providing relief, it can stimulate the digestive system and worsen symptoms. Understanding why this happens involves looking at the complex ways coffee interacts with the gut.

How Coffee Affects the Digestive System

Coffee's impact on the gastrointestinal tract is multifaceted and goes beyond simple caffeine content. Several mechanisms contribute to its laxative effect, which is the opposite of what's needed for managing diarrhea.

Increased Gut Motility: Coffee is a known motility agent, meaning it causes muscles in the digestive tract to contract. This wave-like muscle movement, called peristalsis, moves food through the intestines. When you have diarrhea, this process is already accelerated. Adding coffee can speed it up even further, preventing the colon from absorbing sufficient water and resulting in even looser, more watery stools.
Hormonal Stimulation: Coffee triggers the release of digestive hormones like gastrin and cholecystokinin (CCK). Gastrin stimulates the stomach to release acid, while CCK increases the production of bile and pancreatic enzymes. These hormonal responses kick the digestive system into high gear, which is not ideal during an episode of diarrhea. The stimulating effect is so potent that some studies suggest caffeinated coffee increases colonic activity by as much as 60% more than water.
Acidity: The acidic nature of coffee can irritate the stomach lining and increase acid production, which can exacerbate conditions like acid reflux and general stomach upset. This irritation can contribute to the overall gastrointestinal distress associated with diarrhea. Darker roasts, while popular, can be more bitter and acidic.
Caffeine's Diuretic Effect: Caffeine is a diuretic, meaning it increases urine production and can lead to dehydration. This is particularly concerning during a bout of diarrhea, where the body is already losing significant fluids and electrolytes. Dehydration can worsen fatigue and make recovery more difficult.
Additives and Sensitivities: What you add to your coffee can also play a role. For those with lactose intolerance, adding milk or cream can cause gas, bloating, and exacerbate diarrhea. Artificial sweeteners used in sugar-free products can also have a laxative effect.

Why Decaf Coffee Isn't a Safe Alternative

For those who are sensitive to regular coffee's effects, switching to decaffeinated might seem like a good idea. However, the stimulating properties of coffee are not solely dependent on caffeine. Studies show that decaf coffee can also stimulate bowel movements, though often to a lesser extent than its caffeinated counterpart. This suggests that other compounds, such as chlorogenic acids and polyphenols, are also at play. Therefore, even decaf should be avoided when dealing with an upset stomach and diarrhea.

Comparison: Coffee vs. Diarrhea-Friendly Beverages


Feature	Coffee (Caffeinated)	Decaf Coffee	Diarrhea-Friendly Beverages (Water, Broth, Herbal Tea)
Effect on Gut Motility	Increases significantly	Increases, but less so than caffeinated	Neutral or soothing
Diuretic Effect	Strong, promotes dehydration	Minimal	Neutral, promotes hydration
Effect on Stomach Acidity	Increases acid production	Increases acid production	Neutral or reduces irritation
Best for Diarrhea	No, can worsen symptoms	No, still has stimulating effects	Yes, aids in hydration and recovery
Additives	Additives like dairy or sugar substitutes can worsen symptoms	Additives can still be problematic	Minimal or none needed

What to Consume Instead of Coffee When You Have Diarrhea

Focusing on gentle, binding foods and proper hydration is the most effective strategy for recovery. Medical professionals often recommend the following dietary adjustments:

Stay Hydrated: Drink plenty of fluids to replace lost water and electrolytes. Options include water, clear broth, and electrolyte-enhanced drinks.
Follow the BRAT Diet: This classic diet of bland foods includes Bananas, Rice (white), Applesauce, and Toast. These starchy, low-fiber foods can help firm up your stool.
Include Probiotics: Probiotics, found in some yogurts or supplements, may help restore a healthy balance of gut bacteria, although more research is needed on their immediate effect on diarrhea. It's wise to opt for non-dairy probiotic sources if you are sensitive to lactose.
Eat Small, Frequent Meals: Consuming smaller portions throughout the day can prevent overwhelming your digestive system.

Foods and Drinks to Avoid

Just as important as knowing what to consume is understanding what to avoid. To give your digestive system the best chance to recover, stay away from:

Caffeine and Alcohol: Both are stimulants and can lead to dehydration and increased gut motility.
Dairy Products: Many people experience temporary lactose intolerance during diarrhea, and dairy can worsen symptoms.
Fatty, Fried, and Spicy Foods: These are difficult to digest and can irritate the bowels.
High-Fiber Foods (Temporarily): While fiber is generally healthy, insoluble fiber can exacerbate diarrhea. Foods like whole grains, nuts, and some raw vegetables should be limited during recovery.
Artificial Sweeteners: Sugar alcohols in diet drinks and candies can have a laxative effect.

Conclusion: The Correct Course of Action for Diarrhea

In summary, the notion that coffee helps in stopping diarrhea is a misconception. Its stimulating effect on the digestive tract, caused by a combination of caffeine, acids, and other compounds, is precisely the opposite of what's needed for recovery. During a bout of diarrhea, the best approach is to avoid coffee, stay well-hydrated with water and electrolytes, and stick to a bland, low-fiber diet. By giving your digestive system a break from irritants, you can support a quicker and more comfortable recovery.

For more information on what to eat and avoid during a diarrhea episode, consult reputable health sources like Medical News Today.(https://www.medicalnewstoday.com/articles/320124)

Frequently Asked Questions

No, it is not recommended. While decaf coffee contains significantly less caffeine, it still has other compounds that can stimulate bowel movements and increase gut motility, which can worsen diarrhea symptoms.

Coffee can cause diarrhea due to its stimulating effects on the gut. It increases muscle contractions in the colon, releases digestive hormones, and its acidity can irritate the stomach, all of which speed up the digestive process and result in loose stools.

For effective relief and hydration, opt for fluids like water, clear broth, herbal teas (non-caffeinated), and electrolyte-enhanced drinks. These help replace lost fluids and minerals without stimulating the digestive tract.

Yes, especially if you have lactose intolerance. The sugar in milk (lactose) can be difficult to digest for some, causing or worsening diarrhea and bloating when consumed.

The BRAT diet consists of Bananas, Rice (white), Applesauce, and Toast. These foods are bland, low in fiber, and can help bind stools and ease digestion during a bout of diarrhea.

It is best to reintroduce coffee gradually. Once your bowel movements have returned to normal and your stomach feels settled, you can try a small amount to see how your body reacts. Some people with sensitive digestive systems may need to limit or avoid coffee long-term.

Yes, you should also avoid other caffeinated beverages like black tea, green tea, energy drinks, and some sodas, as they can have a similar stimulating and diuretic effect on the digestive system.