Ill ness as consequence of consuming food containing a noxious agent. Food poisoning is frequently associated with gastroenteritis but, in the wider context of food safety, illnesses other than those involving the digestive tract should be included. A wide variety of agents cause food poisoning, but they can be considered in two broad classes: biological, and chemical. Biological agents are those than can grow and replicate in the body, and it is this growth that results in illness. Illnesses resulting from growth of organisms in the body are infections.