12 Reasons Why You Have Nausea After Eating

No one likes feeling sick to their stomach, especially when you just finished a really good meal. But if you’re feeling nauseated within minutes or hours after eating, there may be something going on underneath the surface.

Gastroenterologist Christine Lee, MD, helps us nail down some of the reasons behind why nausea happens after eating and what you can do to ease your symptoms.

Why you might have nausea after eating

There are many situations that trigger nausea, and this can make it difficult to figure out its exact cause. Some common causes could be related to stress, food allergies, food poisoning, unwanted side effects from medications, taking too many supplements or vitamins, or pregnancy, to name just a few. Gallbladder, liver or pancreatic disease, or diabetes and thyroid disorders can also contribute to feeling sick after chowing down on your favorite foods.

Dr. Lee offers 12 reasons you may be feeling nauseated.

1. Viral or bacterial infection

Ever heard of someone catching a stomach bug? This is just that: If you’ve caught a viral or bacterial infection, your whole body is going to go through it. You might experience nausea right after eating, generally lasting 24 to 48 hours, but you may likely experience a whole slew of other symptoms, too, like fever, muscle aches and joint pain.

“It generally affects your whole body,” says Dr. Lee. “This comes on quick and it usually goes away on its own.”

2. Food poisoning

You can have a physical reaction to eating rotten food. This can happen if you leave food (like meat or dairy products) out for too long, or your food has been mishandled or contaminated by whoever’s preparing the food. Food poisoning sets on suddenly. Luckily, nausea from food poisoning resolves on its own, as well.

“Vomiting or having diarrhea is not always a bad thing in some situations,” says Dr. Lee. “It’s your body’s way of getting rid of the offending agents like an infection, toxins and other things before they’re absorbed.”

3. Food allergies

Food allergies affect everyone differently. In most cases, the first time you experience a food allergy, you may have mild symptoms. Every encounter after that can escalate much faster and cause a more intense reaction. Some examples of allergic reaction symptoms include breaking out in a rash or hives, feeling cold and clammy, a drop in blood pressure, increased heart rate and swelling of your eyes and throat in addition to nausea (or you might not feel nauseated at all).

4. Stress and anxiety

Your body can have physical reactions to stress and anxiety even if it’s been simmering for days on end. The reason you may experience physical symptoms like nausea is that your brain’s “fight or flight” response kicks in, dumping a ton of hormones into your bloodstream that forces your body to react. And everyone has varying levels of this threshold.

“Let’s say two people are watching a movie. One person enjoys horror movies but the other person is terrified,” says Dr. Lee. “The stress hormones that are activated are different between the two people. One can experience increased heart rate or other physical changes like nausea while the other is simply enjoying the movie.”

5. Acid reflux

You can get heartburn shortly after eating, especially when you’ve been eating spicy foods or a greasy or heavy meal. This burning sensation in your upper chest and throat can also sometimes cause nausea.

Acid reflux happens because there’s a large amount of stomach acid that gets splashed back up into your esophagus (throat) and it lingers there. For many, it’s normal and not a sign of anything clinically wrong. Gastroesophageal reflux disease, or GERD, is when your esophagus is harmed from excessive exposure to stomach acid resulting in chronic irritation, inflammation, ulcers and more.

6. Irritable bowel syndrome

Sometimes, your intestines just don’t move the way they need to. If you have irritable bowel syndrome (IBS), you may have issues moving stool through your intestines. It may move too fast or slow even though your colon is structurally normal.

“If your irritable bowel syndrome is acting up and you have stool stored in your colon, then your nausea can get worse because what doesn’t go down will eventually come up,” explains Dr. Lee.

One way to identify if you have IBS is to ask yourself where the pain is coming from. If you reach for your chest or throat, you may have acid reflux. But if you reach for your belly button, your bowels may be the issue.

7. Overeating

“Your stomach can only hold so much,” says Dr. Lee. “Once your stomach is full and food is still sitting there and you continue to eat, you’re going to feel nausea.”

Overeating can occur when “eating while bored.” Instead of eating when you’re hungry, you tend to reach for snacks and other things out of habit, out of boredom or while multitasking.

“There’s so much distraction when we live busy lifestyles, so more and more people are grabbing things on the go and we’re not able to discern what we’re eating, when we’re eating or how much we’re eating,” notes Dr. Lee.

You can avoid this by trying to stick to a routine and setting aside time to have regular meals whenever possible. It’s also helpful to plate your food (vs. eating directly out of a bag or box) to maintain portion control.

8. Medications

Some medications like neurological medications, anti-seizure medications, diabetes medications and mood-altering medications can affect your appetite and eventually lead to nausea. Other common medications that cause nausea are opioid-based narcotics and other pain medications.

9. Diabetes

Having too high or too low blood sugar can cause nausea, as well. But if you’ve had a long history of diabetes, even if it’s well-controlled, you can also develop what’s called diabetes-related gastroparesis (previously referred to as diabetic gastroparesis). This means your stomach doesn’t operate and move the way it should, and digesting food can be a slow process.

10. Gall bladder disease

You can thank your gall bladder for the ability to eat all those greasy foods you love. The bile created by your liver is stored in your gall bladder. Your gall bladder then releases that bile to break down fatty foods. When you have gall bladder disease, this important process can be disrupted and lead to nausea and other symptoms.

If you have gall bladder disease, you might experience nausea 15 to 20 minutes after eating, and it’s generally accompanied by abdominal pain, diarrhea, changes in stool (poop) color and sometimes unexplained weight loss.

11. Pancreatitis

This condition can happen as a result of gallstones, alcohol use, autoimmune disorders and other reasons. Your pancreas goes to work creating enzymes to break down food every time you’re eating, but if your pancreas is inflamed or damaged, it might not create enough enzymes to get the job done.

“Disorders of the pancreas can result in abdominal pain, nausea, diarrhea and unexplainable weight loss,” says Dr. Lee.

12. Chronic mesenteric ischemia

Also known as intestinal ischemic syndrome, this condition is caused when blood flow to your digestive organs is compromised. This can be caused by a buildup of plaque in your arteries or from hardening of your arteries, as well as prolonged low blood pressure, arterial inflammation and more.

Those who are more at risk for this condition include people who are older who have a smoking history, high cholesterol or other vascular disorders like coronary artery disease or peripheral vascular disease, to name a few.

How do you stop nausea after eating?

Nibbling on saltine crackers, small amounts of ginger and resting up — these are all things Dr. Lee calls conservative management. You shouldn’t try treating yourself or doing too much, but if you’re not feeling well, there are some small things you can do to ease the “sick” feeling of nausea.

The most important thing you can do is keep yourself hydrated and get rest. Plus, you should monitor when you’re feeling nauseated, what brought it on, how long it lasts and what made it feel better. This is all important information that can help your doctor determine a diagnosis.

“If it keeps coming back or fails to improve or resolve on its own, it’s not normal and you should get it checked out,” advises Dr. Lee.