How to check the allergen of food allergy

If you want to check food allergens, the currently clinically recognized and reliable methods are mainly skin prick tests, serum-specific IgE tests, and when necessary, food avoidance challenge tests. In addition, bioresonance, hair and nail tests, etc. basically have no scientific basis, so there is no need to spend money.

Not long ago, I met a mother in the outpatient clinic with her 3-year-old baby. The baby was sallow and skinny. She said her baby's mouth turned red after drinking fresh milk half a year ago. She searched online for a service that could test allergens by mailing her nails. She spent nearly 2,000 and found out that her baby is allergic to more than a dozen things including rice, wheat, eggs, and milk. In the past six months, she dared to feed her some millet and cabbage. As a result, her baby's development was half a step slower than her peers. I did a skin prick and serum IgE test on my baby. Except for the slightly higher specific IgE of milk protein, all other indicators were normal. When I went back, I changed the milk to deeply hydrolyzed milk powder and ate eggs as a staple food. In half a month, I gained two pounds, which made my mother regret it.

At this point, someone may ask, what is the difference between these two routine tests, and which one should I choose when going to the hospital? In fact, skin pricking is very convenient. You just drop a small amount of common food extracts on the inside of your forearm, and gently rub the surface of the skin with a special small needle. The results can be obtained in 15 minutes, and the price is cheap. The only thing to note is that you should not take antihistamine-based anti-allergic drugs 3 to 7 days before the procedure, otherwise it will inhibit skin reactions and give false negative results. If you are taking anti-allergic drugs and cannot stop it, or you have sensitive skin that is prone to false positives, you can choose a serum-specific IgE test, which simply draws a tube of venous blood. It is not affected by the drug and the results are more stable. However, you have to wait two or three days for the results to come out, and the price will be higher.

But there is also a point that is still clinically controversial: Does testing positive for IgE of a certain food mean that it must be allergic to it? Many cautious doctors will recommend avoidance of food taboos directly, and many doctors will pay more attention to the actual consumption reaction - I have met many people who were tested positive for eggs and dust mites, but they have eaten eggs for 20 or 30 years without any problems, and they usually have no allergic symptoms. In fact, this is because the body has established immune tolerance, and there is no need to avoid food taboos. If you just stop eating based on the test results, you will be prone to malnutrition.

If you have both negative results from both routine tests, but you get rashes, diarrhea, or even out of breath every time you eat certain foods, especially if you have a delayed allergy where symptoms don’t appear until several hours after eating, you can try the food avoidance provocation test, which is currently recognized as the gold standard for allergen diagnosis in the industry. To put it bluntly, you should first completely stop the suspicious food for 2 to 4 weeks. After the symptoms have completely subsided, you can then try eating these foods in small doses to see if the symptoms will recur. However, if you have had severe allergic reactions such as laryngeal edema and anaphylactic shock before, do not try it at home. You must do it in a hospital with emergency conditions to avoid danger.

To be honest, don’t panic before going for a check-up. Keep a food diary for 3 to 7 days in advance. Remember everything you eat every day and how long after eating it, any symptoms occur. This can be used as a reference for the doctor. It is much more effective than asking for dozens or hundreds of allergens to be checked, and you can also save a lot of wasted money.