Allergen Food Group Report

There are currently 8 core groups of foods with high allergenic risk confirmed in domestic clinical trials, covering more than 90% of food allergy cases. However, due to differences in geography, genetics, and dietary structure, the allergen spectrum of different groups of people varies greatly. There is no "fasting list" that applies to everyone. Allergy diagnosis must be based on a comprehensive judgment based on individual medical history and provocation test results. Blind fasting based on a single test result alone is not advisable.

Last week when I was outpatient at the allergy department, I met a mother who was clutching a "100-item food intolerance test report" purchased on an e-commerce platform. Her face turned pale and she said that her 3-year-old baby couldn't even eat rice or wheat. She had only been fed cabbage porridge for the past half month, and the baby was so thin that his chin was pointed. I looked through the report and found that the so-called "intolerance" tests were all for IgG antibodies, which can only be used as a reference in clinical practice and cannot be directly used as a basis for allergy diagnosis. Finally, I did an oral provocation test. The baby ate the steamed buns with great enjoyment, and there was no problem at all.

They are the milk, eggs, aquatic products such as fish, shrimps and crabs that we often hear about, nuts, soybeans, wheat, peanuts, and shellfish with hard shells. These 8 categories are the core highly allergenic food groups recognized by the Food and Agriculture Organization of the United Nations and are used globally. However, in the past two years, there have been calls from domestic academic circles to add stone fruits such as mangoes and peaches, as well as buckwheat to the core group. After all, the proportion of buckwheat allergy in European and American people is less than 0.1%, and it can reach 1.5% in East Asians. The number of cases of mango allergy in the south has long been higher than that of peanut allergy, and it is not applicable to impose Western standards. I once met a patient from Shanxi who was allergic to buckwheat hull pillows. He developed hives as soon as he touched them. He immediately recovered after changing the pillows. This situation is not mentioned at all in European and American guidebooks.

When it comes to testing, we have to mention "Is food IgG testing an IQ tax" that is causing a lot of controversy on the Internet? This matter really cannot be killed with a stick. The mainstream view is that IgG antibodies only mean that you have been exposed to this food, and are not a sign of allergies. ； However, there are also clinical studies with small samples showing that some patients with chronic urticaria and long-term diarrhea who cannot find clear IgE allergens have significant relief of their symptoms after fasting from high-IgG foods. My personal habit is to ask the patient to compare it with the food diary. If you feel really uncomfortable after eating a certain high-IgG food, then stay away. If you eat something and it's okay, just eat what you should, and don't make trouble with your mouth.

There is another piece of trivia that many people don’t know: the allergenic proteins in many foods are heat-labile. Last year, I treated a high school student who was allergic to raw peanuts. His throat would swell after eating one. However, eating fried peanuts and peanut butter did not cause any problems. This is because the high temperature destroys the allergenic protein. There are also those who are allergic to peach hairs, and it will be fine if they are peeled and eaten. Those who are allergic to raw tomatoes will still taste good after being fried. Don’t just black out a certain food as soon as you see a positive mark on the test report. It’s not a loss.

On an interesting note, our department conducted an allergy survey in three northern provinces last month and found that the proportion of residents in Inner Mongolia who are allergic to milk is nearly 40% lower than that in coastal areas. It is most likely that they have been drinking it since childhood and their immune tolerance is well established. This is why you should not just copy the European and American allergy feeding guidelines. People recommend adding peanut butter to high-risk babies at 4 months old to prevent allergies. Our domestic peanut allergy rate is already more than half lower than that in Europe and the United States. Blindly feeding small-month-old babies is risky. The domestic guidelines have not changed yet, so it is correct to listen to local doctors.

By the way, don’t think that allergy is just a rash that itches twice. A severe immediate allergy can cause laryngeal edema and suffocation in a few minutes. It’s really not a scare. The year before last, I met a young man who ate unmarked chopped peanuts in a takeaway. He was out of breath on the way. Fortunately, a passerby sent him to the hospital in time to save him. If you have been diagnosed with a severe food allergy, don't bother carrying an epinephrine pen with you. It can really save lives at critical moments.

Allergies are too personal anyway. Someone else’s delicious food may be your “death reminder”. There’s really no need to copy other people’s avoidance lists. If you really suspect that you have a food allergy, just keep a food diary for a week. Write down what you eat every day and whether you feel any discomfort. Take it to a regular hospital to see an allergist. It will be more reliable than reading 100 popular science articles in Xiaohongshu. Oh, by the way, I sincerely advise you not to buy that kind of home test kit that claims that one drop of blood can detect hundreds of allergens. The results will most likely be inaccurate and it is a waste of money.