Foodborne illness can affect anyone who eats contaminated food; however, certain populations are more susceptible to becoming ill with a greater severity of illness. These populations include infants and children, the elderly, pregnant women, people taking certain kinds of medications or immune suppressed. Symptoms of foodborne illness include upset stomach, abdominal cramps, nausea, vomiting, diarrhea, fever, and dehydration; they can range from mild to severe and death. To prevent foodborne illness, it is necessary to understand how food becomes unsafe to eat and what proactive measures can be taken to keep food safe. Pathogens can cause different types of foodborne illness. Once a contaminated food is eaten, illness can be caused by the pathogens themselves, caused by toxins produced in the food by pathogens and caused by toxins produced in the body by pathogens.