Stomach Flu Vs. Food Poisoning: How To Tell The Difference

Food Poisoning Or The Stomach Flu? How To Tell And Treat

March 5, 2021 Updated April 29, 2021

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This article has been medically reviewed by Howard Orel, MD. Board-certified and a Fellow of the American Academy of Pediatrics, Dr. Orel runs an active general pediatric practice, Advocare Marlton Pediatrics. He also serves as CEO of Advocare — one of the largest independent medical groups in the country. 

Nausea. Indigestion. Upset stomach. Diarrhea. No, this isn’t a Pepto-Bismol commercial. Is it the stomach flu? Is it food poisoning? Ugh, who cares? Just make the torture stop. When curled up in the fetal position in bed or the bathroom floor, all that matters is how to treat it and how long it will last. Thankfully, while some notable differences exist between stomach flu vs. food poisoning, the symptoms — and treatment — are very similar. However, having an idea of what caused your gastrointestinal distress will help keep your family from getting themselves or others sick. 

Of course, when in the throes of said illness, you need answers fast. This explainer should help you quickly narrow down the cause of your illness. 

What causes the stomach flu?

“Stomach flu” is not an actual medical condition but a common term for all kinds of gastroenteritis. These viral infections attack the digestive system and cause inflammation to your stomach and intestines. The influenza virus, which causes the flu, is a respiratory illness and has nothing to do with the stomach flu. So, the flu shot won’t help the stomach flu one bit — but now you can seem extra cerebral the next time someone incorrectly compares influenza and the stomach flu. 

Several viruses cause the stomach flu, but norovirus is the most common. It is highly contagious and can be spread through touching a shared surface, having direct contact with someone who has the virus, and even eating or drinking contaminated food or beverages handled by an infected person. The Center for Disease Control says norovirus is the leading cause of foodborne illnesses in the United States. Maybe you, too, have horror stories about your norovirus-infected kid puking all over you and themselves. 

What causes food poisoning?

Bacteria is usually to blame for food poisoning. Foods like undercooked poultry, dairy products, greens, and seafood can cause food poisoning if not handled properly. It often happens to everyone who eats the contaminated food (misery loves company). However, it is possible to experience food poisoning with no symptoms. 

The top five germs that cause foodborne illnesses, and what leads to their proliferation, are: 

  • Norovirus: Having direct contact with an infected person, consuming contaminated food or water, or touching contaminated surfaces and then putting your unwashed hands in your mouth (wash those hands!). Norovirus is tough and can live on surfaces for up to four weeks.
  • Salmonella: Usually transmitted by eating food contaminated with animal feces. Gross.
  • Clostridium perfringens: Can be found on foods kept at an unsafe temperature. 
  • Campylobacter: Eating raw or undercooked poultry or eating something that touched it.
  • Staphylococcus aureus (Staph): When people with Staph don’t wash their hands before touching food.

What are stomach flu symptoms?

One big way to tell the difference between stomach flu and food poisoning is the onset of symptoms. Unlike food poisoning, stomach flu symptoms may take a day or two to come on and build up over time. These symptoms include:

  • Watery diarrhea (most common)
  • Stomach cramps
  • Nausea
  • Vomiting
  • Low-grade fever
  • Dizziness

What are food poisoning symptoms?

Symptoms from food poisoning usually come on dramatically. But blaming the “last meal you ate” might not be the source of the poisoning. Symptoms can start anywhere between under an hour and three weeks between consuming contaminated food, but once they hit, they hit hard. For example, E. coli can take about 10 days to present symptoms. That sneaky b****. Keep all of this in mind before publicly shaming last night’s takeout dinner on Yelp.  

You might experience a combination of symptoms, including:

  • Nausea (most common)
  • Vomiting (most common)
  • Watery diarrhea
  • Stomach cramps
  • Fever
  • Headache
  • Gas

Some less common symptoms include blurry or double vision, muscle aches, bloody diarrhea, and even constipation. 

What is the recovery time for each? 

Most cases of food poisoning and stomach flu pass without needing medical attention. Typically, the stomach flu lasts a few days. For some, it can last multiple weeks.

Food poisoning usually comes and goes quickly depending on your age and overall health. Expect food poisoning recovery time to last 24 to 48 hours. It might take a few more days to get back to full strength. If your symptoms persist with no improvement after 48 hours, see a doctor.

What’s the best course of treatment?

When it comes to treating stomach flu vs. food poisoning, the recommendations are the same.  

Stay Hydrated

When you’re sick, it’s tough keeping contents in your stomach. Dehydration can become a big problem. Borrow your kid’s Pedialyte or drink Gatorade or Powerade to help you stay hydrated. 

Don’t Force-Feed

Wait until vomiting has stopped for at least an hour before eating. Avoid alcohol, smoking, spicy and fried foods. 

BRAT Diet

When you’re ready to try eating, keep it simple with unseasoned foods like Bananas, Rice, Applesauce, and Toast. 

Get Lots of Rest

Whether food poisoning or stomach flu, it might take a little time to feel like yourself again. The less stress you put on your body, the quicker you will recover. 

Antibiotics

Prescription medicine may cure food poisoning from bacterial infections. Unfortunately, stomach flu sufferers are out of luck. Antibiotics can’t kill viruses. 

How can you avoid food poisoning and the stomach flu? 

  • Wash your hands. 
  • Wash your food.
  • Wash cutting boards and knives regularly to avoid cross-contamination. Keep raw meat far away from other foods and cook food to the correct temperature.
  • Separate sick family members. Gastrointestinal illnesses are very contagious. It’s best to quarantine until a few days after symptoms pass. 
  • If your food doesn’t look right, don’t eat it. Say goodbye to last week’s delicious sandwich. Your nose will also help you sniff out something rotten. Trust it. 

How do I disinfect my house after stomach flu?

To ensure a virus-free future, it’s important to deep clean your home after someone has had the stomach flu. Here are a few ways to rid your house of any lingering infection.

  • When cleaning, wear disposable gloves.
  • Wipe the house down with disinfectant or bleach. (Be careful with the bleach, make sure to dilute it with water and air out your home during use.) Leave the cleaning solution on the surfaces for at least seven minutes. Then wipe it down and clean it again with soap and water. After cleaning the toilet and indoor surfaces, tackles the doorknobs, light switches, telephones, and remote controls too.
  • Wash everyone’s sheets and the sick person’s clothes in separate washes.

Stomach flu vs COVID-19

Since the pandemic, when any illness sets in, it’s important to make sure it isn’t a sign of coronavirus. So, if you’re having symptoms of the stomach flu, and worried it might be COVID-19, here are a few signs and similarities to look out for.

COVID usually affects your respiratory system, but people have reported gastrointestinal issues as well. In about five to 10 percent of adults with COVID-19, they’ve reported nausea, vomiting, or diarrhea. If a person experiences stomach issues, it could just be a stomach bug. But, if it’s accompanied by dry coughing and difficulty breathing, it may be COVID. Be on the lookout for fever and shortness of breath throughout the week. That’s usually a good sign to get tested for coronavirus.