Content

• Steps
• Part 1 of 3: Observation Diary
• Part 2 of 3: Elimination Diet and Challenge Test
• Part 3 of 3: Allergen Tests
• Tips
• Warnings

If you suspect you have an allergy, there are several ways to find out which foods are causing it. In this article, we'll show you how to determine the cause of your allergy.

Steps

Part 1 of 3: Observation Diary

1. 1 If you are unsure of which foods are causing allergic reactions, keep a diary for 2-3 weeks. By writing down the ingredients of every meal you eat and the subsequent reactions of the body, you can associate certain foods with allergies. Once you understand what could be the cause of your allergy, you can eliminate these foods from your diet and get tested for a specific allergen.
2. 2 Write down everything you eat and drink. It is important to have a complete list of all foods.
   • Eat as usual - just carry a small notebook with you to journal not only the main meals, but also any snacks during the day.
   • Write down all the ingredients. For example, if you are eating homemade oatmeal cookies, write down the ingredients; keep the packaging if the cookie was purchased. This will help you narrow down the possible allergens and understand what exactly is causing the reaction. In the future, you can test your guesses by excluding certain foods from the diet.
3. 3 Record the duration, nature and intensity of allergic reactions. Sometimes, intolerances to certain foods can be mistaken for allergies, and short-term reactions may indicate the wrong food.
   • Record all symptoms: itching, swelling, pain or heaviness in the abdomen, diarrhea, fever, colic and other manifestations of the skin and digestive tract. This will allow you to determine the type of sensitivity and choose how to deal with the manifestations of food intolerances or food allergies.
4. 4 Discuss your observations with your dietitian or allergist. If you have an observation diary, it will come in handy at your doctor's appointment. Thanks to it, the doctor will be able to recognize allergens and give nutritional advice.

Part 2 of 3: Elimination Diet and Challenge Test

1. 1 After you have gathered information about your diet and symptoms discussed above, and show this information to your doctor, you should try an elimination diet. Such a diet means avoiding certain foods. If you have an anaphylactic reaction to food, do not use this diet or perform an oral challenge test without medical supervision.However, if you only have moderate-intensity reactions, a diet or test can help narrow down the list of possible allergens.
2. 2 Make a list of foods that you will eliminate from your diet. Re-read your observation diary and cut down on food that you associate with an allergic reaction, or reduce its consumption.
   • Going on a very strict diet and eliminating more than five ingredients is only recommended if you suspect you are allergic to a common ingredient (such as lactose or plant protein).
3. 3 Strictly follow the diet for 1-4 weeks. Continue to keep a diary of observations. If the symptoms are completely gone, return to the diet one food per week and continue monitoring.
   • If the food you put back in your diet does not cause reactions, cross it off the list of possible allergens. Then return the next product. Continue observing until any of the food begins to cause allergic reactions. After this happens, re-exclude this product from the diet and observe your condition.
   • Responsibly approach the issue of excluding certain products. For example, if you think honey might be causing your allergies, check the ingredients of any foods that may contain honey and read the ingredient list on labels for cookies, sweet nuts, iced tea, etc. If you often eat convenience foods, make sure there are no ingredients that are potentially harmful to you.
4. 4 Monitor your body's response to foods you return to your diet. Make a list of the foods that are causing the symptoms and then show them to your doctor before testing for allergens.
   • If an allergic reaction is caused by a food containing more than one ingredient, write down the complete composition of that food, including all food additives, preservatives, and colors. You may think that you are allergic to applesauce, mustard, or soda, but in fact the reaction can be caused by a seasoning, color, or sugar substitute.
5. 5 Repeat the experiment until you have identified possible allergens. If the intensity and frequency of symptoms decrease, it will indicate that you were able to identify the main allergens, or that you were unable to recognize the allergens hidden in the prepared food.
   • If you need help putting together a diet plan, see an allergist. Your doctor may look at your food list and observation diary and advise you on specific tactics.
   • For example, an allergist can categorize potential allergens (for example, pitted fruits or emulsifiers in sauces), notice cross-contamination with allergens (this is often the case with nuts or grains), or incomplete exclusion of allergens (due to the implicit presence of an ingredient in a convenience food or different names of the same ingredient).
6. 6 Perform an oral challenge test. If you have swelling, rash, and signs of anaphylactic shock after eating certain foods, do not do this test yourself - see your doctor.
   • An oral challenge test consists of eating a small amount of food that may cause allergies, then increasing the portion at regular intervals. If a small amount does not cause an allergic reaction, the serving is increased.
   • In an oral challenge test, only one allergen at a time is considered for accuracy. More than one test per week can only be performed in the presence of an allergist.

Part 3 of 3: Allergen Tests

1. 1 To verify the conclusions, take tests for allergens. Identifying food allergens is often very difficult.If you've already kept a diary, tried an elimination diet, or had a provocative test, donate blood or have allergen skin injection tests. If you usually have mild allergic reactions, it is the combination of methods that will most accurately determine the cause of the allergy. The collection of information obtained by all means will help to identify the main allergens.
2. 2 Make an injection test. This is a simple and quick procedure that can be done with your regular doctor's appointment.
   • An injection test is the injection of a small amount of an allergy-causing substance under the skin. Any skin reaction means the body's sensitivity to the allergen.
3. 3 Donate blood for allergens. Blood tests reveal many more allergens than injection tests, and often more accurately determine the true cause of an allergy (injection tests can only reflect the body's reaction to contact with food).
   • A blood test for allergens involves taking a small amount of blood and testing it in a laboratory. The analysis may take several weeks to complete. You will receive a printout listing all the products that were tested during the research, with the result for each of them.

Tips

• If you want your child to keep a diary of observations, ask the school teacher to help you and make sure that the child does not eat foods that he should not eat.
• A simple allergen test can identify the root cause of most food allergies. Test for IgG antibodies to a panel of food allergens.

Warnings

• Don't become a hypochondriac. Sometimes, in the desire to be different from others and to stand out from them due to a special food allergy, you can find symptoms in yourself that in fact do not exist. If in doubt about your symptoms, see your doctor so as not to speculate.
• Some foods can cause severe allergic reactions that require epinephrine to be administered. If you or your child has had anaphylactic reactions, do not try to identify the allergen yourself.