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Food Poisoning Health Center

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Understanding Food Poisoning -- the Basics

What Is Food Poisoning?

You can get food poisoning after eating food contaminated by viruses or bacteria. 

Other types of food poisoning can be caused by parasites or exposures to toxins or chemical agents. 

Understanding Food Poisoning

Find out more about food poisoning:



Diagnosis and Treatment


Food poisoning causes anything from mild to severe acute discomfort and may leave you temporarily dehydrated. 

Mild cases may last only a few hours or days, but more serious types, such as botulism or certain forms of chemical or toxin poisoning, are severe and possibly life-threatening unless you get medical treatment.

What Causes Food Poisoning?

Many bacteria can cause food poisoning. People who are ill or infected can transmit staphylococcus bacteria to food they are preparing. People who eat or drink contaminated food or water can get travelers' diarrhea, usually caused by the bacterium E. coli. Salmonella poisoning can occur from eating contaminated poultry, eggs, and meat; though potentially fatal, most cases cause only mild symptoms. Harmful bacteria grow in cooked and raw meat and fish, dairy products, and prepared foods left at room temperature too long.

Canned goods, especially home-canned produce, can harbor a bacterium that needs no oxygen to multiply and is not destroyed by cooking. This bacterium causes botulism, a rare but potentially fatal food poisoning. Infants may develop botulism from eating honey because their immature digestive systems, unlike those of adults, cannot neutralize its naturally occurring bacteria.

Raw seafood, especially contaminated shellfish, may bring on food poisoning. Certain mushrooms, berries, and other plants are naturally poisonous to humans and should never be eaten; potato sprouts and eyes also contain natural toxins. Toxic mold can form on improperly stored fruit, vegetables, grains, and nuts. Deadly toxins are contained in certain types of mushrooms. Chemical food poisoning can be caused by pesticides or by keeping food in unsanitary containers.


WebMD Medical Reference

Reviewed by David T. Derrer, MD on April 05, 2014

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