What Causes Chronic Diarrhea After Eating?

Woman holding her stomach in pain
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Diarrhea is never pleasant, and when it happens right after eating, it becomes hard to enjoy a meal. You may become wary of what to eat and anxious about eating anything at all. Any new or ongoing digestive symptom should be brought to the attention of your doctor so that you obtain an accurate diagnosis and treatment plan. Chronic diarrhea after eating may be a sign of a serious health condition.

While you are waiting to see your doctor, it might be helpful to learn about some of the most common causes of chronic diarrhea after eating, as well as to become acquainted with some self-care strategies for addressing the problem.

Note: If your diarrhea after eating is a brand-new and severe problem, please see this article:

Chronic Diarrhea After Eating Causes

Diarrhea after a meal is known formally as postprandial diarrhea. There are a wide variety of health problems that have chronic diarrhea as a symptom.  If you have one of these disorders, the simple act of eating a meal may serve as a trigger for diarrhea episodes.

As you can see, the reasons behind the symptom of diarrhea can vary widely depending on your diagnosis. Addressing the underlying illness can help to bring about relief from the symptom of running to the bathroom after meals.

Irritable bowel syndrome (IBS): Just the simple act of eating can be enough to set off the symptom of diarrhea in some people who have IBS.

It is not clearly known why there is such a hyperreactivity of the digestive system in this disorder.

Lactose intolerance: People who have lactose intolerance lack sufficient amounts of the enzyme necessary to break down lactose, a sugar found in milk and milk products. This can cause the symptom of diarrhea after consuming dairy foods.

Sugar intolerance: In addition to lactose, some people are unable to digest the sugars fructose, found in many fruits and high fructose corn syrup, and/or sorbitol, also found in some fruits as well as artificial sweeteners. Such an intolerance can be identified through the use of breath testing or an elimination diet.

Celiac disease: People who have celiac disease experience an autoimmune reaction in response to ingesting gluten, a protein found in wheat, rye, and barley. Diarrhea from celiac disease is often odorous and stool may be more likely to float rather than sink. Celiac disease has serious health consequences, so if you are experiencing chronic diarrhea after eating, you should speak with your doctor about being screened for the disease.

Inflammatory bowel disease (IBD): The two forms of IBD, Crohn's disease, and ulcerative colitis, can both cause the symptom of diarrhea after eating. The diarrhea of IBD may include signs of blood in the stool.

Bile acid malabsorption (BAM): Bile acids are secreted by your gallbladder in order for your digestive system to digest fats.

When these acids are not re-absorbed properly they affect the working of your large intestine, resulting in diarrhea. Sometimes the cause of BAM is unknown, other times it occurs following surgery or illness involving your digestive organs. Some researchers believe that BAM may be the underlying cause of IBS for some people.

Gallbladder removal: Without a gallbladder, some people experience a problem with poor regulation of bile acids into the small and large intestines, causing similar symptoms as BAM.

Dumping syndrome: This syndrome is most commonly experienced by people who have undergone bariatric surgery for weight loss. Dumping syndrome is also known as rapid gastric emptying, because the contents of the stomach empty too quickly into the small intestine. Therefore, eating, particularly meals with a high sugar content, can trigger off symptoms such as diarrhea.

Microscopic colitis: This type of colitis is a distinctly different illness than ulcerative colitis. With microscopic colitis, inflammation in the cells lining the intestines can only be seen when tissue is looked at under a microscope. The cause of microscopic colitis is not well known. Its symptoms include persistent or intermittent episodes of watery diarrhea.

What to Do for Chronic Problems with Diarrhea After Eating

1. Tell your doctor! Any unusual symptom should always be brought to the attention of your doctor. This helps to ensure that you receive a proper diagnosis and therefore a helpful treatment plan can be developed. 

2. Follow your doctor's orders to best manage your underlying health problem.

3. Eat small meals throughout your day and avoid fatty foods, such as fried food, fatty meats, and thick gravy. Large meals and fatty foods can increase the strength of intestinal contractions and thus prompt a diarrhea episode.

4. Use relaxation exercises to calm your body. Due to the close connection between your brain and your gut, stress can be a trigger for diarrhea. Most of us deal with a lot of stress in our lives, not to mention the fact that having diarrhea after your meals is stressful! Click here to learn how.


"Diarrhea" Mayo Clinic Accessed January 23, 2013

"Diarrhea" Medline Plus Accessed January 23, 2013.

"Diarrhea" National Digestive Diseases Information Clearinghouse (NDDIC) Accessed January 23, 2013.

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