Diarrhea is a common condition with many possible causes. Some cases of diarrhea are due to infections. Sometimes it occurs as a side effect of medication, or as a symptom of other conditions, such as celiac disease and inflammatory bowel disease.
This article focuses on foods that can cause diarrhea. Learn about foods that cause diarrhea, how to tell if diarrhea is due to something that has been eaten, treatment options, and when to see a doctor.
Foods that could cause diarrhea:
1. Sugar and sugar substitutes
Foods that are high in sugar can cause diarrhea. When people eat foods that contain a lot of sugar, water enters their intestines, which can result in very loose stools.
Fructose is a component of table sugar and is also found naturally in fruits. Some fruits contain more fructose than others. Some examples of foods high in fructose include:
- apple juice
The body can only digest a certain amount of fructose at one time. Consuming more fructose than the body can absorb, may cause diarrhea.
Dr. Norton Greenberger, a gastroenterologist and Harvard Medical School professor, states that "75 percent of people who ingest more than 40 to 80 grams of fructose per day will get diarrhea."
Another source estimates that approximately 30 to 40 percent of people have trouble absorbing significant amounts of fructose.
Sugar alcohols, including sorbitol, mannitol, xylitol, and erythritol, are commonly used to sweeten foods labeled "sugar-free" or "no sugar added." These sugar alcohols are not well absorbed by the body and can cause diarrhea in some people, especially if consumed in large amounts.
People should be sure to check the ingredients list of foods labeled "sugar-free" or "no sugar added," such as chewing gums, candy, and protein bars, to see if they contain any sugar alcohols.
Drinks and foods that contain caffeine can cause diarrhea in some people. Caffeine is a stimulant and accelerates the rate that food moves through the intestines.
Common dietary sources of caffeine include:
3. High-fat and spicy foods
Fried foods and other foods that contain a lot of fat can cause diarrhea because they are difficult for the body to process.
Although it is no longer commonly used by the food industry, a fat substitute known as Olestra can cause diarrhea. People should check labels of fat-free products, such as potato chips, to see if it lists Olestra as an ingredient.
Spicy foods, such as those that contain hot peppers, are another common cause of diarrhea.
People who are lactose intolerant may experience diarrhea, in addition to other symptoms, after they consume dairy products. Lactose intolerance is prevalent among African-Americans, Asian-Americans, Mexican Americans, and Native Americans.
Some people with lactose intolerance may be able to tolerate small amounts of dairy products that are aged or those that are lower in lactose. These products include yogurt, kefir, and hard cheeses.
Fermentable oligosaccharides, disaccharides, monosaccharides, and polyols are a category of carbohydrates called FODMAPs. High-FODMAP foods are difficult for some people to digest and may cause diarrhea.
Some categories already mentioned in this article, like fructose, lactose, and sugar alcohols, are considered FODMAPs. The list of high-FODMAP foods is extensive, but a few other examples include:
A low-FODMAP diet can be challenging to follow due to a large number of restricted foods. If someone thinks that FODMAPs may be the cause of their diarrhea, a registered dietitian can provide education and guidance.
Gluten is the protein in wheat, rye, and barley, and many of the people who have problems digesting it have a serious illness, such as celiac disease. When someone has celiac disease, their immune system reacts to gluten and triggers damage to the small intestine.
People that do not have celiac disease may still have issues tolerating gluten. If someone suspects that gluten may be responsible for their diarrhea, it is important that they see a doctor for proper testing before starting a gluten-free diet.
Diarrhea could be food-related if a person has recently made changes to what they eat. It could also be related to food if a person notices that a particular food or type of food, such as dairy products, causes diarrhea.
Keeping a food and symptom diary can be helpful for determining a pattern.
Diarrhea is unlikely to be related to food intolerance if it:
These are signs that may signify a more serious condition.
If someone has diarrhea, they should continue to consume a regular diet as tolerated. Historically, doctors have recommended the BRAT diet (bananas, rice, applesauce, and toast) for treating diarrhea, but there is no solid evidence to prove its usefulness.
Also, people do not need to restrict dairy products unless they suspect that dairy has caused their diarrhea. Listed below are some treatments and remedies that may be helpful for diarrhea.
Keeping hydrated is a top priority when someone has diarrhea, and the best way to achieve this is to drink plenty of fluids.
In addition to water, Stanford Cancer Nutrition Services also recommend that people with diarrhea can sip on any of the following:
- caffeine-free tea
- diluted juice
- drinks that contain electrolytes, such as sports drinks
- flat ginger ale
Fluids that have both sugar and salt, called oral rehydration solutions (ORS), are easier for the body to absorb. According to the American Academy of Family Physicians, people can make an ORS by adding half a teaspoon of salt and 6 teaspoons of sugar to 1 liter of water.
Over-the-counter medications are also available to help treat diarrhea. People should check with their doctor to work out if a store-bought medicine is appropriate for them.
Some studies have shown that loperamide (Imodium) and simethicone bring more relief when taken together than individually.
Bismuth subsalicylate, better known as Pepto-Bismol, is another medication available from a drugstore.
Probiotics are the beneficial bacteria that live in the gut. They may be a helpful treatment for children with diarrhea, but more studies in adults are needed.
While foods that are high in insoluble fiber can worsen diarrhea, foods that contain soluble fiber can help promote more formed stools.
Some examples of foods that are high in soluble fiber include oats and oranges.
When to see a doctor for diarrhea
The American College of Gastroenterology recommends seeing a doctor if diarrhea continues for longer than 48 hours. Also, people should see a doctor if diarrhea contains blood, is accompanied by severe stomach pain, or if they do not feel well.
Infants and older adults are more prone to dehydration, which means that diarrhea can be particularly dangerous for people in these groups. It is important to look out for signs of dehydration in these groups, such as:
- a reduced amount of urine
- increased heart rate
- dizziness or confusion
Many cases of mild, short-term diarrhea resolve on their own. Treatment and home remedies can help ease the discomfort associated with diarrhea.
Written by Megan Metropulos, MS, RDN & Megan Ware, RDN, LD