If you’re feeling sick (nauseous) after eating a big meal or something you don’t usually eat, you probably don’t need to worry too much. Nausea is quite common, and usually goes away on its own.
Lots of things can make you feel sick. You might have an infection or a bad headache (migraine), for example. But it can be caused by what you eat. You might also feel discomfort in your tummy, and lose your appetite.
Read on to learn why you might feel sick after eating, when to see a doctor, and things you can try to ease nausea.
What causes nausea after eating?
If you’re feeling sick after a meal, 2 common possible causes are food poisoning and a stomach bug (gastroenteritis). Here’s what you should know about both these conditions.
Food poisoning
Food poisoning is fairly common, and symptoms usually come on a few hours or days after you’ve eaten food that’s contaminated with germs. As well as feeling sick, you might be sick (vomit), have tummy cramps, loose poos (diarrhoea) or a high temperature, and feel generally unwell.
While the symptoms can be unpleasant, food poisoning is rarely serious, and you’ll usually feel better within a week without treatment.

Gastroenteritis
Often referred to as a stomach bug, gastroenteritis is a gut infection which is when the lining of your stomach, small and large intestines becomes inflamed. It’s usually caused by viruses, bacteria and parasites, and you can get it from eating contaminated food.
The symptoms of gastroenteritis can come on suddenly and, as well as nausea, often include vomiting, diarrhoea, loss of appetite and pain in your tummy.
Like food poisoning, gastroenteritis can be very uncomfortable, but usually goes away on its own in less than a week.
Other potential causes
If you don't think feeling sick is related to food poisoning or gastroenteritis, there are some other common causes.
Looking at other symptoms you may have may help you work out what’s wrong. Here are some symptoms, and what they might mean if you have them with nausea:
- heartburn (a burning feeling in the chest) or bloating – it could be acid reflux, when stomach acid travels up towards your mouth
- headache and a high temperature – it could be flu
- bad headache and increased sensitivity to light and sound – it could be a migraine
- dizziness – it could be an inner ear infection that affects your balance (labyrinthitis) Read more about other causes of dizziness and nausea
Other causes of nausea are pregnancy, motion sickness, anxiety, medication and alcohol.
When to see a doctor
Although feeling sick is rarely a sign of anything serious, being sick (vomiting) can occasionally be a symptom of a more serious problem. If you're feeling very unwell, or are worried about vomiting, seek medical help.
It’s also a good idea to speak to your doctor if:
- you don’t feel better after a few days
- you often feel nauseous
- nausea keeps coming back

Things to try at home to ease nausea
- go outside to get some fresh air
- try to distract yourself – listen to music or watch a movie
- sip a cold drink, such as water
- drink ginger or peppermint tea
- snack on foods containing ginger (ginger biscuits)
- eat smaller meals, more frequently

Key points
- feeling sick (nausea) after eating is rarely serious, and usually goes away on its own
- food poisoning and gastroenteritis are 2 common causes
- other symptoms, such as heartburn or a headache, can suggest other causes
- speak to your doctor if you don’t feel better after a few days, or you often feel sick