On average, it takes 4-36 hours to get food poisoning after ingesting infected food.
More Info: The time it takes for food poisoning to affect the body varies greatly depending on the type and cause of the poisoning. It can hit almost immediately within the hour or can fester up to four weeks. Typical symptoms of food poisoning will appear within 12-72 hours.
Common Food Poisoning Causes and Incubation Periods
Following are common bacteria and toxins that cause food poisoning including the accompanying symptoms, foods likely to carry the bacteria or toxin, and the average time of onset of symptoms.
Symptoms: Vomiting, diarrhea, headache, and fever
Associated Foods: Particularly widespread in poultry and pork. Any raw meat, milk, eggs, peanut butter, coconut, fish, shrimp, and yeast.
Onset Time: 6-48 hours
Symptoms: Severe abdominal cramping, diarrhea with more blood than stool
Associated Foods: Raw hamburger, raw milk, unpasteurized fruit juices, game meat, and lettuce.
Associated Foods: Many foods that are preserved improperly.
Onset Time: 18-36 hours
“Bad Bug Book: Introduction.” U S Food and Drug Administration Home Page. N.p., n.d. Web. 5 Oct. 2010. <http://www.fda.gov/Food/FoodSafety/FoodborneIllness/FoodborneIllnessFoodbornePathogensNaturalToxins/BadBugBook/default.htm>.
“Food poisoning.” University of Maryland Medical Center. N.p., n.d. Web. 5 Oct. 2010. http://www.umm.edu/altmed/articles/food-poisoning-000064.htm.