Food Poisoning | Causes & Risk Factors


What foods are most likely to cause food poisoning?

Raw or undercooked meat or poultry, unpasteurized dairy products, raw shellfish, unwashed fruits and unwashed vegetables most commonly cause food poisoning.

Food poisoning is more common at picnics and buffets, where food (such as the mayonnaise in potato salad) is often left out of the refrigerator for a long time.

How do you get food poisoning from fish?

There are two ways to get food poisoning from eating fish:

  • Ciguatera (say: “seeg-wha-terra”) poisoning: This happens when you eat a reef fish (any fish living in warm tropical water) that has eaten a certain poisonous food. This poison does not go away when the fish is cooked or frozen.
  • Scombroid poisoning: A substance called histamine builds up in some fish when they get too warm after they’re caught. Histamine is a chemical that serves as a kind of alarm to let your immune system know that an infection is attacking part of the body. If you eat a fish that was not properly cooled after it was caught, you may react to the histamine that is released into your body.

Who is at greater risk of getting food poisoning?

Children and the elderly are most likely to get food poisoning. You may also be at a higher risk if you:

Have recently traveled to areas outside the United States where you may have had greater exposure to germs that can cause food poisoning.


Poisoning, Envenomation, and Trauma from Marine Creatures by RA Perkins, M.D., M.P.H. and SS Morgan, M.D. (American Family Physician February 15, 2004,

Written by editorial staff

Reviewed/Updated: 04/14
Created: 09/00