Foods Causing Highest IgG Immune Response in Saudi Arabia

Background: Type III hypersensitivity caused by immunoglobulin G (IgG) to food has elicited plenty of scholarly attention in recent years. Opinions continue to be divided regarding the linkage between IgG reactivity to food and chronic inflammatory diseases.

Objective: To identify foods that cause the maximum amount of IgG immune reaction in patients throughout Saudi Arabia from a standardized food panel and to identify any difference caused by age or gender.

Methods: We used a pre-existing database for patients who participated in the standardized panel of 268 foods ELISA-based IgG to conduct a food allergy test referred to as ImuPro™ Complete. The data in the database was prepared by the database provider through the utilization of established procedures from R-Biopharm AG using standard ELISA plates. Meanwhile, the samples were processed in ELISA Washer and Reader machines. Readings were analyzed using R-Biopharm’s standard ImuPro™ software and then fed into the database used by us.

Results: A total of1644 patients (913 males and 731 females=55.5% male, 44.5% female) were tested. IgG reactivity was predominant in eight foods (3%) in at least three-quarters of the studied population. These included Oats (82.5%), Barley (79.1%), Rye (76.1%) Cow’s Milk (75%), Wheat (74.9%), Kamut (74.6%), Spelt (74.6%) and Gluten (73.9%). The IgG immune response of males and females to each food type was found to be almost the same. Children have a significantly different IgG food profile in comparison to adults (p-value =0.024). Cow's milk was found to induce the highest IgG immune response among children below five years of age (95.74%), followed by oats (92.2%).

Conclusion: To the best of our knowledge, this is one of the largest studies to have been conducted worldwide that involves the IgG immune response of patients to food. The top-most foods were ‘mainstream’ foods consumed almost daily, which include gluten and dairy products. No significant difference was found between males and females. A clear difference can be seen between children and adults when it comes to the IgG immune reaction to different food items. Further investigations are recommended to determine the food characteristics and eating habits that cause these IgG immune responses.