In the stomach, food tends to hang around for a little longer and this depends on a variety of factors including the amount of food you have consumed, how much fat it contains, and also the acidity of the stomach. However, all food should have left the stomach within 2 to 4 hours.
Many factors can affect body temperature. Illness, Disease and Trauma. Fever can be caused by infection or illness; this is the bodyâs way of fighting the infection. Certain diseases, such as arthritis, hyperthyroidism and leukemia may also cause elevated body temperature.
Fever or a high temperature is usually a normal response to an infection as the body fights it off. Part of the brain called the hypothalamus may decide to regulate the body's temperature to a higher level. Common causes of fever are: 1  Colds and flu. 2  Gastroenteritis stomach bugs.