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What causes nausea after eating? Related conditions and treatments

Although the occasional bit of nausea after eating isn’t a cause for concern, you should see your healthcare provider if it occurs after every meal

Key takeaways

Chances are, you know the feeling. You ate a little too much of something a little too spicy, and now your stomach is upset, you feel a little sick as if you might vomit, and you’re looking for a bathroom. You’ve got nausea after eating, and you’re pretty sure you’re going to have diarrhea, too. It happens to just about everyone from time to time.

But what, exactly, causes nausea after eating? You’ve had other big, spicy meals that didn’t upset your stomach. What made this meal different? The answer could be that you ate too much or you couldn’t handle the spice, but nausea can also be a sign of an underlying medical condition that could be a problem. If nausea after eating is starting to become a regular occurrence, talk to a doctor or other health care professional to ensure it’s not a sign of something serious.

What causes nausea after eating?

Nausea after eating is one of the body’s defense mechanisms, letting you know that you’ve ingested something that the body perceives as unpleasant or possibly toxic (or that you’ve ingested too much of something nontoxic). The medical processes that lead to nausea aren’t well understood. Still, they involve the release of enzymes in the gastrointestinal tract and the central nervous system in response to stimuli that the body sees as a threat. Common causes of nausea after eating include:

  • Overeating When you eat more than your stomach can handle, all that food disrupts your digestive system, causing indigestion and nausea. In severe cases, it can cause vomiting as your stomach tries to relieve internal pressure.
  • Food allergies or intolerance – When you are allergic to or intolerant of certain foods, your body has trouble digesting them, making you feel nauseous. Food allergies can also cause a rash or hives, swelling of the eyes or throat, increased heart rate, a drop in blood pressure, or anaphylaxis.
  • Food poisoning – Rotten or contaminated food can contain viruses, bacteria, parasites, toxins, or molds that make toxins. Eating contaminated food can give you E. coli, Salmonella, Campylobacter, norovirus, or another foodborne illness, leading to symptoms like nausea, vomiting, diarrhea, fever, and stomach pain. 
  • Motion sickness or morning sickness – If you are already susceptible to getting seasick or carsick, eating a meal beforehand can sometimes make the nauseous feeling worse. Likewise, for pregnant women who already feel sick in the morning, eating something may make nausea worse.
  • Viral or bacterial infection – Flus, colds, respiratory illnesses, and other infections that affect the entire body can cause nausea and lack of appetite. Sometimes called a “stomach bug” or “24-hour flu,” some infections can bring on nausea and other symptoms for a day or two before resolving on their own.
  • Stress and anxiety – When you’re feeling stressed or anxious, it revs up your body’s fight-or-flight instinct, and your body responds by upping your hormone levels and releasing chemicals that can trigger nausea and other symptoms like an increased heart rate and restlessness (the jitters). Moments of high anxiety—like a critical game or a big performance—can cause “butterflies in the stomach” and, in severe cases, vomiting.
  • Medications – Many types of prescription and over-the-counter (OTC) medications can affect your appetite and cause nausea when you do eat something. The list includes medicines used to treat cancer (chemotherapy), as well as antibiotics, opioid pain medications, Advil (ibuprofen), Aleve (naproxen), aspirin, antidepressants, and vitamin and mineral supplements, especially if taken on an empty stomach. 
  • Acid reflux – Medically known as gastroesophageal reflux (GER), acid reflux happens when stomach acid and the contents of your stomach come back up into your esophagus. This can cause a burning sensation in the throat, heartburn, regurgitation of food, nausea, and vomiting. Gastroesophageal reflux disease (GERD) occurs when someone has recurring GER or GER that is causing other symptoms or complications.
  • Irritable bowel syndrome (IBS) – Doctors aren’t sure what causes IBS, a common disorder that can affect the entire digestive tract, but the symptoms include bloating, abdominal pain, gas, nausea, and changes in bowel movement frequency or consistency (constipation or diarrhea). These symptoms typically become more pronounced after eating. 
  • Diabetes – According to the Centers for Disease Control and Prevention (CDC), diabetes is the most common cause of gastroparesis, a condition in which high blood sugar leads to nerve damage in the stomach muscles, making the affected muscles slow down or stop working. This can affect how fast your body digests food and can keep your stomach from emptying properly, possibly causing nausea as new food is added to your stomach.
  • Pancreatitis – Every time you eat, your pancreas creates enzymes that help your body digest food. Pancreatitis (inflammation of the pancreas) disrupts the pancreas and affects the body’s ability to break down food properly. This can lead to nausea and vomiting after a meal. Pancreatitis can be caused by gallbladder disease, gallstones (gallstone pancreatitis), heavy alcohol use, genetic disorders of the pancreas, or as a side effect of some medicines.
  • Chronic mesenteric ischemia – Mesenteric ischemia is a condition in which blocked or narrowed arteries restrict blood flow to the small intestine. Over time, decreased blood flow can permanently damage the small intestine and affect the digestive process. This can lead to belly pain and nausea shortly after and can cause food to not be broken down properly.
  • Inflammatory bowel disease (IBD) – With ulcerative colitis or Crohn’s disease, the two forms of IBD, a malfunction in the body’s immune system leads to the development of sores (ulcers) and inflammation in the large intestine (ulcerative colitis) or anywhere in the GI tract (Crohn’s). This can lead to symptoms like nausea, diarrhea, bloody stool, and abdominal pain that can be more severe after a meal. 

Should I be worried about nausea after eating?

Almost everyone will feel nauseous after a meal at some point in their lives. In many cases, it resolves without treatment in a day or two, and that’s the end of it. But if you get nauseous after every meal or more than every once in a while, it could be a problem.

“Nausea can be a sign of a serious health problem and will need to be addressed by a healthcare provider if it is persistent,” says Carol Murakami, MD, a gastroenterologist and spokesperson for the American Gastroenterological Association. Although persistent nausea itself doesn’t lead to many long-term problems, the condition causing the nausea may harm the body if it goes untreated.

Although rare, severe cases of nausea after eating may require immediate medical attention, especially if they are accompanied by vomiting and dehydration. “If a patient cannot keep anything down, or they have persistent nausea for unclear reasons, they should seek medical attention,” Dr. Murakami says.

Nausea after eating can be a sign of a medical emergency if it is accompanied by chest pain, severe abdominal pain or cramping, blurred vision, high fever, stiff neck, rectal bleeding, severe dehydration, or vomit that contains blood or resembles coffee grounds. In such cases, call 911 or immediately get the affected person to an emergency room.

How is the cause of nausea after eating diagnosed?

If you seek medical attention for nausea, the doctor will ask you questions about your recent history, such as what you’ve eaten and what sort of activities you’ve been doing, to rule out causes like overeating, food poisoning, stress, and motion sickness. If the doctor determines that your nausea after eating is most likely the result of an underlying condition, they will look for other symptoms to help them decide what tests to conduct. 

“Diagnostic tests ordered depend on the patient’s symptoms other than nausea,” Dr. Murakami says. “For example, if a patient has nausea with abdominal pain and fever, they may order a CT scan of the abdomen and pelvis to take a closer look for evidence of inflammation, such as colitis or diverticulitis.”

If you have a pre-existing condition that can cause nausea after eating, such as diabetes, IBS, GERD, IBD, or chronic mesenteric ischemia, your healthcare provider will likely see if there is a relationship between the condition and your nausea before exploring other causes. 

How long does nausea after eating last?

In many cases, such as overeating and food intolerance, nausea after eating will go away once the meal that caused it has been digested. 

“Nausea created by overeating will usually only last until your body has had sufficient time to digest and move the food through the intestinal tract,” says Tami Best, a registered dietitian with Top Nutrition Coaching. “Although this can vary depending on the content of the meal.”

Other times, nausea may last a day or two as a stomach bug or other illness runs its course through your GI tract. But if you have a chronic underlying condition, you could feel nauseous after every meal. 

“The duration of nausea after eating depends on the root cause,” Dr. Murakami says. “It can be very persistent depending on what is causing the nausea. Patients with gastroparesis or delayed emptying of the stomach can be nauseated 24/7.”

How to treat nausea after eating

In most cases, mild nausea after eating doesn’t require any special treatment, although you should stay well hydrated and eat only bland foods until the nausea subsides. You may also consider OTC antiemetic medications such as Pepto-Bismol (bismuth subsalicylate).

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“High-fat foods, spicy foods, and acidic foods tend to make nausea worse,” Dr. Murakami says. “Changing your diet to a low-fat, bland diet can be helpful, as well as avoiding acidic beverages such as orange juice and lemonade.” 

Eat small portions of food throughout the day rather than having three big meals to aid your digestion, and consider adding more ginger to your diet. “Ginger—in capsule form, tea, cubes, or fresh root—is a fabulous home remedy for nausea,” Best says.

Persistent nausea after eating is treated by treating any underlying causes. This can often include eating a healthier diet, keeping in good physical health, and knowing which foods to avoid.

“Foods that individuals sense they have an allergy or intolerance to are most likely to cause nausea,” Best says. “Common intolerances are gluten, dairy products, food additives, and fermentable carbohydrates.”

Most importantly, see a doctor for persistent nausea after eating

Feeling nauseous after eating is not typically a cause for concern if it happens every now and then. Nausea caused by overeating, food sensitivity, motion sickness, or anxiety should pass quickly and resolve without treatment.

However, if you have persistent nausea after eating or feel sick after every meal, it could be a sign of a potentially serious underlying condition such as GERD, IBS, diabetes, pancreatitis, chronic mesenteric ischemia, IBD, or a viral or bacterial infection that requires treatment. 

Only your healthcare provider can rule out infection or other serious health conditions. Visit your doctor to determine the best treatment for nausea after eating.

 

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