Causes of Food Poisoning

Each year, millions of people in the United States get sick from contaminated food. Symptoms of food poisoning include upset stomach, abdominal cramps, nausea and vomiting, diarrhea, fever, and dehydration. Symptoms may range from mild to severe.

	Bacteria and Viruses Bacteria and viruses are the most common cause of food poisoning. The symptoms and severity of food poisoning vary, depending on which bacteria or virus has contaminated the food.
	Parasites Parasites are organisms that derive nourishment and protection from other living organisms known as hosts. In the United States, the most common foodborne parasites are protozoa, roundworms, and tapeworms.
	Mold, Toxins, and Contaminants Most food poisoning is caused by bacteria, viruses, and parasites rather than toxic substances in the food. But, some cases of food poisoning can be linked to either natural toxins or chemical toxins.
	Allergens Food allergy is an abnormal response to a food triggered by your body's immune system. Some foods, such as nuts, milk, eggs, or seafood, can cause allergic reactions in people with food allergies.