In normal naked healthy subjects there are skin temperature variations over the skin surface. Qualitatively and quantitatively these variations will depend on many factors including the thermal state of the subject as well as ambient temperature. Apart from the abdominal region, and to some extent the female breast, the human body is thermally symmetrical. That is, variations in skin surface temperature are very similar on the left and right side of the body.

This fact is of particular use when using Medical Thermography as a diagnostic tool, where the appearance of an asymmetric thermal image (thermogram) may be indicative of a pathological conditions.  While asymmetrical pathological conditions often occur a problem arises if the pathological conditions in question is equally affecting similar sites on both sides of the body. Here a knowledge of what a thermogram in a normal healthy subject should look like is important. Unfortunately, a complete data base containing thermograms of normal healthy subjects at different ages and sexes is not yet available. However, scientists at the University of Glamorgan, Wales, UK have taken steps to rectify this and are in the process of constructing such a database.