Food Poisoning Signs and Symptoms

Even healthy foods can make you sick if they're tainted with germs. Foodborne illnesses are fairly common—in fact, according to the Centers for Disease Control and Prevention, about 48 million people get sick from foodborne illnesses each year. About 128,000 of those people are hospitalized, and roughly 3,000 die.

Man clutching his stomach
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Foodborne illness is often referred to as food poisoning, but most of the time it's caused by bacteria, viruses, or parasites. Actual toxins or poisons, which are not as common, include botulinum and norovirus. The usual bacterial suspects are:

The signs and symptoms of bacterial foodborne illness include digestive system complaints and usually start a day after you eat contaminated food. But it may take as long as a few days for the symptoms to start, which can make it difficult to pinpoint which food made you sick.

Here's what you might be feeling if you've eaten something that's tainted:

  • Abdominal cramps
  • Diarrhea
  • Fever
  • Nausea
  • Vomiting
  • Headache
  • Weakness
  • Abdomen is tender to touch
  • Dehydration

Do I Need to Go to the Hospital?

It's a good idea to see a doctor if you have unusually severe symptoms, but many people just stay home and wait it out. Infants and young children, pregnant women, seniors, and individuals with weakened immune systems need medical attention for food poisoning. Anyone else should seek care if the food poisoning signs don't improve after a day or two.


The best way to prevent foodborne illness is to avoid contaminated foods, which isn't always easy—especially when you eat in a restaurant. But there are some things you can do to reduce your risk of foodborne illness at home:

  • Wash your hands before cooking, before serving and before eating meals.
  • Keep raw meat, eggs, and poultry away from any other foods that are ready to be served.
  • Use clean knives, utensils, and cutting boards, and don't cross-contaminate raw meats and poultry with fruits and vegetables.
  • Wash fresh fruits, vegetables, and bagged greens.
  • Keep perishable foods at 40 degrees Fahrenheit or less.
  • Beef, lamb, poultry, and pork should be cooked to proper internal temperatures.
  • Leftovers should be heated to 165 degrees before serving.
  • After they're heated, hot foods should be kept at 140 degrees or above.

The number of cases of food poisoning goes up during the summer months, when bacteria grow faster in the warmer temperatures. Since summer is a great time for picnics and barbecues, be sure to follow food safety rules for transporting and storing foods outdoors.

When Food Poisoning Is Really Due to Poison

Food poisoning is usually caused by bacteria, but ingesting poisonous foods—such as certain mushrooms or shellfish, or eating seafood harvested from contaminated water—can cause similar symptoms. These forms of food poisoning are an emergency, and you should seek treatment immediately.

3 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control and Prevention. Foodborne Illnesses and Germs.

  2. U.S. Department of Agriculture. Foodborne Illness: What Consumers Need to Know.

  3. Lima AD, Costa fortes R, Carvalho garbi novaes MR, Percário S. Poisonous mushrooms: a review of the most common intoxications. Nutr Hosp. 2012;27(2):402-8. doi:10.1590/S0212-16112012000200009

By Shereen Lehman, MS
Shereen Lehman, MS, is a healthcare journalist and fact checker.