Because patients with food intolerance produce food-specific IgG due to an excessive protective immune response to one or more types of food, a blood test for food-specific IgG levels can be used to confirm the presence of food intolerance. Depending on the type of food, it can be categorized into the traditional 14-item test and the full 90-item test. Depending on the concentration of food-specific IgG, the test results can be categorized as "negative, mild intolerance, moderate intolerance, and severe intolerance", and dietary regimens can be selected based on the results of the test: safe, alternating, or fasting.

14 tests: beef, peanuts, chicken, pork, cod, rice, corn, shrimp, crab, soy, egg whites/yolks, tomatoes, mushrooms, wheat.

90 tests: Brussels sprouts, lobster, lemon, lima beans, malt, millet, almonds, mushrooms, American cheese, mustard seeds, apples, oats, avocados, olives, bananas, onions, whole barley, oranges, beef, oysters, lingonberries, parsnips, cabbage, peaches, buckwheat, peanuts, butter, mixed peas, cabbage, pineapple, cane sugar, pork, cantaloupe, potatoes, Carrots, rice, cashews, rye, cauliflower, safflower seeds, celery, salmon, cheddar cheese, sardines, chicken, scallops, red peppers, sesame seeds, chocolate, river prawns, cinnamon, sole, clams, soybeans, cod, spinach, coffee, pumpkin, cola beans, strawberries, corn, green peas, white cottage cheese, sunflower seeds, milk, sweet potatoes, crab, Swiss cheese, cucumber, black tea, egg whites/yolks, tobacco, Eggplant, tomatoes, scallions, salmon, goat's milk, tuna, grapes, turkey, glazed seeds, black walnuts, tender peas, wheat, green peppers, bread yeast, halibut, brewer's yeast, honey, and yogurt.