It’s not pleasant to talk about, and it’s even less pleasant to deal with, but everyone experiences watery stools (a.k.a. diarrhea) occasionally. Most bouts of diarrhea are caused by a virus or bacteria, but certain foods, including dairy, coffee, and anything spicy, can also send you running for the bathroom. Show
And despite feeling embarrassing, it’s a common issue. Research shows that up to 5% of U.S. adults are dealing with chronic diarrhea at any one time; another 2018 survey of 71,000 Americans revealed that up to one in five people have experienced diarrhea in just the past week. What causes diarrhea immediately after eating?If you’ve ever had to run to the toilet after eating, you’ve experienced acute diarrhea. Although there are a number of possible causes, including malabsorption, intolerances to foods like dairy, and chronic conditions like irritable bowel syndrome (IBS), it’s likely that this type of diarrhea is caused by food poisoning or a virus, per the National Institutes of Health (NIH). Food poisoning is the result of ingesting food or water contaminated with bacteria, the NIH notes. Food poisoning symptoms appear between hours and days after ingesting contaminated food, according to the Centers for Disease Control and Prevention (CDC). Illnesses like norovirus and viral gastroenteritis, commonly called the stomach flu, can also cause acute diarrhea; symptoms can appear between 12 hours and 10 days after exposure to a virus, depending on the strain, the NIH explains. What causes chronic diarrhea?Certain food allergies and GI conditions make digestive issues lasting more than a few days more likely. Lactose intolerance, IBS, and celiac disease are three of the most common triggers of chronic diarrhea, according to the NIH. When you eat foods that inflame these conditions, like dairy, high-fiber foods, and gluten, it’s likely that your body will respond with diarrhea. If you suspect that food, rather than an illness, is causing your diarrhea, start paying attention to your eating habits. “The best way to investigate which foods are making your symptoms worse is to keep a food diary,” says Shilpa Ravella, M.D., a gastroenterologist and assistant professor of medicine at Columbia University Medical Center. To do this, write down everything you eat in a day, including serving sizes and any brand names, alongside the time you eat. Then, note when you have symptoms and see if you can ID any common culprits. When you can finally pinpoint the foods that trigger your tummy troubles, you may be able to spare yourself some discomfort—and a few extra trips to the restroom. So, which foods are most likely to cause diarrhea? Ahead, GI doctors share the most common culprits to keep in mind.
Sugar-free snacks and chewing gum may help satisfy your sweet tooth, but many contain sugar substitutes that can also act as a laxative. “Sweeteners such as aspartame, sucralose, and sorbitol can contribute to diarrhea and bloating based on how your body metabolizes them in the gut,” says Bhavesh Shah, M.D., the medical director of Interventional Gastroenterology at Long Beach Memorial Medical Center in California. Is your morning cup promptly followed by a rush to the bathroom? That’s pretty normal. “Coffee can cause diarrhea in some people,” Dr. Ravella says. “The caffeine can stimulate the gut to contract more quickly than it normally does, so food moves through faster and isn’t absorbed as well.” The acidity of coffee can also worsen the symptoms of some digestive disorders, such as acid reflux. Other caffeinated foods and drinks, including tea and energy drinks, could have the same effect. If you have a few too many during a night out (or in, these days!), you may wake up with an upset stomach the next morning. “This is often a symptom that accompanies a hangover,” Dr. Shah says. “Alcohol is an irritant. Your gut may not agree with drinking a large amount.” Booze also speeds up digestion, which affects your body’s ability to absorb water—hence the liquid stools when you’re hung over. According to the National Institutes of Health, up to 50 million American adults may be lactose intolerant. If your stomach goes rogue when you eat milk, cheese, or yogurt, you may be one of them. “Common symptoms, which begin about 30 minutes to two hours after consuming foods containing lactose, may include nausea, cramps, bloating, gas, and diarrhea,” Dr. Shah says. Gluten—a mix of proteins found in wheat, rye, and barley—can cause diarrhea and bloating for some people, but the good news is that a true gluten sensitivity is relatively rare. Still, if you feel like wheat may be wreaking havoc on your digestive system, keep a food diary and look for patterns: Are you sick every time you eat bread or pasta? “If you think you have gluten intolerance, it’s important to see a gastroenterologist to make sure you don’t have celiac disease,” Dr. Ravella says. For people with this disorder, gluten can do serious damage by causing the body to attack the lining of the small intestine. FODMAP stands for fermentable oligosaccharides, disaccharides, and monosaccharides, and polyols. They’re a group of carbs and sugar alcohols that can be tough to digest, especially for people with IBS, Dr. Ravella says, leading to gas, bloating, and diarrhea. A low-FODMAP diet may help improve symptoms, but should be monitored by a dietitian, as it requires you to cut out certain foods rich in vital nutrients, including high-fiber fruits and vegetables, dairy, and grains. Fiber gets your digestive system moving, which is a good thing—but sometimes it’s a little too effective, Dr. Shah warns. Fiber binds with water, which can help prevent constipation but may also have a laxative effect if you consume too much at once. This is why many people who go vegan experience an upset stomach at first; a lot of produce means a lot of fiber. That’s not to say you shouldn’t load up on fruits and veggies, as they keep your gut healthy, help you maintain a healthy weight, and offer important disease-fighting nutrients. Instead, eat more fiber gradually until your stomach adjusts. Some people can eat jalapeños like they’re candy, while others feel their stomach churn at the mere sight of a chile pepper. “Each individual is unique when it comes to tolerating spicy foods,” Dr. Ravella says. “Spicy foods can irritate the lining of the stomach and intestines, causing food to move more quickly through the gastrointestinal tract, which results in loose stools.” If you don’t eat spicy food often, she adds, you’re more likely to feel the burn when you do. If you need motivation to skip the drive-thru window, consider that greasy takeout grub can be hard on your gut. “In general, all fats can be harder to digest, but the worst culprits are greasy, fried foods typically found at fast food restaurants,” Dr. Ravella says. “You’re less likely to have issues when eating healthy fats from whole foods, like avocados.” Greasy fries, on the other hand, don’t really pack any nutritional benefits—so if they bother your belly, just skip them entirely. Seek medical help if you have bloody or black stools, show signs of dehydration, have severe abdominal or rectal pain, have diarrhea for more than two days, or are experiencing a fever, per the Mayo Clinic. Do the same if a child experiences any of these symptoms or has diarrhea for more than 24 hours. Diarrhea is an annoying problem, but it can be a dangerous one, too. Your doctor might not be able to help speed recovery—most cases clear up on their own—but they’ll be able to offer advice on how to make your experience more bearable. You should also contact your primary care physician for help with chronic diarrhea, since they might be able to connect you with a gastroenterologist for further guidance in managing your symptoms and safely altering your diet.
Diarrhea is when someone has loose, watery stools or bowel movements. When this occurs after eating, it is known as postprandial diarrhea (PD), which can happen quite unexpectedly. It can also cause discomfort or pain until a bowel movement occurs. Share on PinterestAdam Sargent/EyeEm/Getty Images PD is relatively common, but it may be difficult to figure out what is causing it and how to treat it. The reason for this is that PD can be a sign of a medical condition, or it can just happen with no specific cause. Diarrhea is either acute or chronic, depending on how long the symptoms last. Acute diarrhea lasts for only a couple of days or weeks. Chronic diarrhea, on the other hand, can last for several weeks or months. This article discusses the causes of both acute and chronic PD, along with what a person can do to treat and prevent them. How often diarrhea occurs can vary greatly and depends on the underlying cause. The following are the prevalence rates of some common causes of diarrhea following eating. A person may not necessarily experience diarrhea, but diarrhea can be a symptom of each condition:
There are many different causes of PD or diarrhea after eating, depending on whether it is acute or chronic. Acute PDAcute diarrhea usually lasts for 1–2 days. Doctors either treat it with medicine or leave it to run its course. Its causes include: Food poisoningContaminated food or water can cause diarrhea. Bacteria, viruses, parasites, or other organisms can cause contamination and lead to illness. Viruses and bacteria are the leading causes of food poisoning in the U.S. InfectionViral gastroenteritis, also known as “stomach flu,” can cause diarrhea and vomiting. “Flu” is a misnomer as this type of infection has nothing to do with influenza. Instead, the most common cause of viral gastroenteritis is norovirus. Gastrocolic reflexGastrocolic reflex is a physiological reflex where consuming food causes the rectum to respond by moving stool. The intensity of the movement can vary between people. Doctors can use this phenomenon to help relieve constipation in children and older people by establishing a routine of passing a bowel movement after eating. It is a relatively common occurrence, but it does not typically cause diarrhea. Lactose intoleranceSome people have an allergy to milk or are not able to digest lactose, which is the sugar in milk. This means that if they drink or eat milk, it can cause diarrhea, cramping, and gas. Lactose intolerance has a higher prevalence rate in people with Asian, African, or Hispanic ancestry compared with those with northern European ancestry. Toddler’s diarrheaAcute diarrhea is common in young children between the ages of about 6 months and 5 years. Although doctors do not know the exact cause, theories include children who experience it moving food through their bowels faster, which does not allow for as much water absorption. Another theory is that it occurs in children who drink a lot of sugary drinks, such as fruit juice. The high amount of sugar causes water to enter the intestines, making the stool more watery. AntibioticsSome antibiotics can cause an upset stomach and acute diarrhea. The symptoms tend to resolve once the person stops taking antibiotics. ParasitesSome parasites can cause acute diarrhea. The symptoms tend to last until a doctor identifies and removes the parasite. These types of parasites are not common in developed countries and people usually contract them while traveling. The most common parasites in the U.S. include roundworm, protozoa, and tapeworms. Chronic PDChronic diarrhea is diarrhea that lasts for at least 4 weeks, with a minimum of three loose or watery bowel movements each day. Potential causes of chronic diarrhea include: Irritable bowel syndromeIBS is a disorder that can cause bloating, cramping, and either constipation (IBS-C) or diarrhea (IBS-D). It is the most common GI disorder, with a 10–15% worldwide prevalence rate. Dietary changes, medication, and stress management strategies can often help a person control the condition. Inflammatory bowel diseaseIBD is an autoimmune condition where the immune system attacks otherwise healthy cells of the intestines, causing inflammation and irritability in the intestines. Crohn’s disease and ulcerative colitis are two examples of IBD. Both can cause persistent diarrhea, cramping, weight loss, and tiredness. Endocrine disordersSome hormonal disorders, such as hyperthyroidism and diabetes, can cause chronic diarrhea, especially if there is nerve damage to the intestinal tract. Celiac diseaseCeliac disease is an autoimmune disorder that affects the absorption of gluten, the protein found in wheat and wheat products. People with this condition have diarrhea whenever they eat food that contains gluten from wheat, barley, or rye. Several products may contain gluten, including pasta, bread, sauces, gravies, and other products a person may not immediately think about. A person should check the label of prepared foods to see if they contain gluten. In most cases of acute diarrhea, the symptoms go away over time, and a person can manage them at home. Home careHome care often includes a combination of hydration, bland foods, and preventing others from getting sick if an underlying illness is a cause. People living with chronic conditions, such as IBD, IBS, or celiac disease, should follow their doctor’s recommendations on diet to help prevent making their symptoms worse. HydrationDiarrhea can lead to dehydration if a person does not replace the lost fluids. People with mild to moderate diarrhea may find the following methods to replace lost fluids helpful:
It is important to use fluids that contain sugar and salt to help replace lost electrolytes. Foods to eatSomeone with acute diarrhea should eat bland foods until their stomach starts to feel better. Bananas, rice, soup, and crackers are particularly easy to digest and can help to harden stools. Hand hygieneHand washing and other hygiene measures provide a crucial step in preventing the spread of the germs that cause diarrhea. According to the World Health Organization (WHO), hand washing with soap can help prevent diarrheal disease by up to 48%. A person should frequently wash their hands with soap and water or an alcohol-based hand rub throughout the day, including:
Medical treatmentTreatment of diarrhea, whether it is acute or chronic, depends on its cause. If an infection is to blame, medication may help. However, sometimes a person just needs rest, fluids, and time. As long as there is no fever or blood in the stools, a person can use over-the-counter (OTC) medications to reduce the frequency of loose stools. These will not cure the cause of diarrhea but can make someone feel better and cut down the fluid loss. Medications include:
If a specific food or substance, such as lactose or gluten, causes diarrhea, it is important for a person to avoid those triggers in the future. When IBD or IBS causes diarrhea, a person may need to use medications to control the immune system or inflammatory reaction. These can include biologics and steroids. A person should follow their treatment plan when taking medications and tell their doctor if these no longer help. Learn more about IBD treatments here. People with diarrhea that do not see improvements with home measures or other treatments within 48 hours should see their doctor. A person should seek medical attention immediately if they experience diarrhea and any of the following symptoms:
A doctor will review a person’s medical history, do a physical exam, and may order additional diagnostic tests. Once the doctor finds the cause of the diarrhea, they can recommend an appropriate treatment. Many kinds of diarrhea are preventable. Hand hygiene can help prevent acute illness, and avoiding trigger foods may help a person living with a chronic condition avoid flares. Some additional prevention methods include:
The following are answers to some frequently asked questions about the causes of diarrhea after eating. What causes yellow diarrhea after eating?Stool color can give some clues to a person’s health. While brown stool indicates the person is healthy, yellow stool could indicate the presence of Giardia, a common parasite. It can also indicate issues with the liver, gallbladder disease, or malnutrition associated with celiac disease. Black or red stools can indicate intestinal bleeding, while green, blue, or orange stools can result from eating foods containing these colors. What causes stomach pain and diarrhea after eating?Several conditions can cause stomach pain along with diarrhea. Some common ones include:
What causes fatigue and diarrhea after eating?People who experience both fatigue and diarrhea likely have an underlying health condition, such as celiac disease or IBD. It is also possible that a person has an acute stomach infection that is causing fatigue as well. What causes diarrhea 6 hours after eating?If a person experiences diarrhea within hours of eating, they may have food poisoning. Symptoms such as diarrhea can occur in as little as a few hours from eating the bad food. It is also possible that a person may have an undiagnosed case of IBS, so they should talk with their doctor if symptoms persist. What causes diarrhea after eating salad?Having a bowel movement or even diarrhea after eating a salad is not uncommon or concerning when no other symptoms are present. Salad and other foods high in fiber can often trigger a bowel movement and possibly even diarrhea since some people do not always digest it well. However, diarrhea after eating a salad could also indicate exposure to contamination from spoiled or improperly washed ingredients. What causes gas and diarrhea after eating fatty foods?In some cases, gas and diarrhea after eating fatty foods may be the result of a person consuming too much. Some underlying conditions, such as gallbladder disease or IBS, can also cause a combination of gas and diarrhea. Can Covid cause diarrhea after eating?Covid can cause gastrointestinal symptoms, including diarrhea. Symptoms typically clear within a few weeks, but they can sometimes last for months or years. In most cases, acute diarrhea will pass through a person’s system within 2 days with or without treatment. During this time, they should stay hydrated and possibly take OTC medication for some symptom relief. While chronic diarrhea may have a more distinct medical cause, such as IBD, the outlook is still good. Treatments, including avoiding certain foods and following a treatment plan, can help improve a person’s outcome. Last medically reviewed on April 20, 2022 Medical News Today has strict sourcing guidelines and draws only from peer-reviewed studies, academic research institutions, and medical journals and associations. We avoid using tertiary references. We link primary sources — including studies, scientific references, and statistics — within each article and also list them in the resources section at the bottom of our articles. You can learn more about how we ensure our content is accurate and current by reading our editorial policy. |