The 90 Food IgG ELISA Test is for measuring the relative amount of food-specific IgG antibody in human serum. The values obtained must always be correlated with the clinical presentation, since elevation of a certain food-specific antibody by itself does not necessarily mean disease. The kit can be used to help diagnose hidden food intolerance as well as to develop elimination diets which along with other clinical information can help in the treatment of Irritable Bowel Syndrome (IBS) and other diseases caused by food intolerance/allergies. This kit does not provide information about IgE-mediated allergies. Specific allergens are immobilized separately onto microtiter wells. The allergens are allowed to react with specific antibodies present in the patient’s serum. Excess serum proteins are removed by the wash step. Enzyme labeled antibody conjugate is allowed to react with allergen-antibody complex. A color is developed by the addition of a substrate that reacts with the coupled enzyme. The color intensity is measured and is directly proportional to the concentration of IgG antibody specific to a particular allergen.