Symptoms can happen in any part of the body, including the stomach and bowels. Food intolerance may cause symptoms similar to food allergy. People who have a food intolerance do not have an allergic reaction. They lack the enzymes needed to fully digest certain foods. This is true for milk.
Many people are unable to process a sugar in milk called lactose.
Lactose intolerance causes stomach cramps, bloating, diarrhea, and gas. Contamination of food by bacteria is called food poisoning. For example, salmonella can contaminate eggs. Heat kills this bacteria, so be sure to cook eggs thoroughly. Avoid dishes that use raw eggs such as hollandaise sauce and high-energy drinks.