To determine the prevalence of wheat sensitivity in a randomly selected Australian population, a study was carried out on sera samples of the Geelong Osteoporosis Study (GOS) age-stratified cohorts of men and women who were randomly selected from electoral rolls for the Barwon Statistical Division (n = 1145). The human sera were analysed by ELISA-based method using the ImmunoCAP 100 instrument (Phadia, Sweden). IgE from human sera were bound to the wheat (f4) and milk (f2) allergens that have been previously coated on the ImmunoCAPs. The number of IgE wheat and milk RAST positive individuals was determined. In order to relate the increased IgE immuno-reactivity to allergen symptoms, a questionnaire was established and sent to the blood donors and 974 individuals responded. Of these (n = 974) 147 individuals (15.1%) reported symptoms caused by wheat consumption, 179 (15.6%) and 112 (9.8%) sera showed RAST positive results (IgE > 60 response units) in wheat and milk RAST tests, respectively. However, only 2.5% of those participants with symptoms related to wheat had positive IgE values indicating that the relationship is complex: a large proportion (12.7%) of the investigated population might suffer from other wheat related disorders (i.e. not IgE mediated), such as celiac disease, non-celiac reaction to gluten, reaction to fructans for those with irritable bowel syndrome as well as other factors. For the 13.2% who showed raised IgE antibody levels without symptoms we postulate that these individuals have latent wheat sensitivity with the potential of developing symptoms sooner or later.A comparative study to investigate the immune reactivity of human IgE against wheat and spelt antigens was carried out using the sera of 73 patients found to be RAST positive for wheat. Of these 63% (n = 50) showed a higher IgE immune reactivity against wheat, while 30% (n = 24) showed higher IgE response against spelt antigens, the remaining 7% have indifferent responses against both antigens. Since the provided Phadia wheat and spelt antigens used in this study originated from Europe, Australian wheat and spelt varieties were also used to prepare antigens in order to investigate the response of Australian sera to local wheats. It was found that the immune reactivity of IgE wheat positive sera from a normal Australian population is lower for spelts compared to wheats regardless of their origin but much lower against an Australian spelt containing a mutation in its expansin gene. A clinical feeding trial would be