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, grapes, agave, soda
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.”
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.
2. Caffeine
As caffeine is a stimulant, it may cause diarrhea. 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: chocolate, coffee, soda, tea
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.
4. Lactose
People who are lactose intolerant may experience diarrhea, in addition to other symptoms, after they consume dairy products.
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.
5. FODMAPs
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: artichokes, beans, garlic, onions
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.
6. Gluten
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.