food allergy taboos

The core principle of food allergy taboos has never been "the more taboos, the safer", but "strictly avoid food after accurately targeting allergens + be vigilant about cross-contact + never blindly expand the range of taboos" - this is the most practical conclusion I have drawn after working in allergy clinics for 6 years and seeing thousands of allergy patients take detours.

Last week, we received a 3-year-old patient. The parents found out that the child's milk IgE was high, so they immediately banned milk, eggs, wheat, and soybeans when they returned home. They even refused to touch any biscuits with a bit of milk flavor. In half a year, the child's growth curve dropped by 20 percentile, and he was as thin as a small bean sprout. When I asked him, I found out that the parents were afraid of "cross-allergy" and had banned all foods that they heard could cause allergies.

Really can't do it.

Nowadays, academic circles have different opinions on the strictness of taboos. One group advocates absolute strict food avoidance. They should not touch anything with allergens, and even processed foods that have been touched on the production line should be eliminated. This group has a strong basis: even if a patient with a history of severe allergies is exposed to microgram-level allergens, it may induce laryngeal edema and anaphylactic shock, which can be really fatal. I once met a college student who was allergic to peanuts. He ate half a piece of nougat given by his roommate, which only contained 1% peanut butter, and was sent to the emergency room for emergency treatment on the spot.

The other school of thought is now becoming more and more accepted: For patients who only have mild to moderate allergic reactions such as rashes and itching, and who have no history of severe attacks, they do not need to have strict lifelong taboos. Oral immune induction can be done under the supervision of a doctor, and small doses of gradual exposure to allergens may build long-term tolerance. Many children who were allergic to milk and eggs when they were young have gradually been able to eat eggs and milk normally through this method, without having to live with cakes and milk tea all their lives.

But no matter which school of thought you come from, the premise must be "accurately targeting allergens", which is also the pitfall that many people are most likely to fall into. Don’t just judge it as an allergy if you have diarrhea or rash after eating something. In many cases, it may be lactose intolerance, food additive irritation, or even just indigestion after eating too much. The food IgG test that is now popular on the Internet is still controversial in the industry as to its reference value. If you really want to check for allergies, you have to combine skin prick testing, serum-specific IgE testing, and a double-blind placebo-controlled food challenge test. This is the gold standard for diagnosis.

I have seen too many people avoid their favorite foods for several years with unreliable test reports. There was a 28-year-old girl who said she was allergic to shrimps and had been avoiding crabs for five years. She came to our place for a provocation test and found out that she was only allergic to a certain protein in shrimps and had no problem eating crabs. She went to a seafood store that day to show off two pounds of hairy crabs and messaged me, saying, "I feel like I have made a huge loss in the past few years."

Another point that is most easily overlooked is cross-contact. Don’t think it’s safe if there are no allergens listed in the ingredient list. If you cut the watermelon on a cutting board that has been used to cut mangoes at home, do not wash it clean. People who are allergic to mango may get rashes after eating watermelon. ； Restaurants outside have fried nut shrimp in oil and then fried French fries. People with nut allergies may also have a reaction after eating French fries. There was a 16-year-old girl who had eaten fried potato wedges in a Western restaurant. The pot had just fried walnut shrimp. She was allergic to walnuts. Her throat was swollen and she couldn't breathe on the spot. It took an ambulance to take her away and rescue her for a long time before she recovered.

So don’t be embarrassed to ask questions when you go out to eat. Tell the waiter clearly about your allergies. When buying packaged food, also take a look at the small print below the ingredient list. The label “This product’s production equipment also processes foods containing peanuts, nuts, and dairy products” is not printed casually.

Of course, there is no need to overdo it. I have met expectant mothers who were afraid that their children would be born with allergies. They did not even dare to touch eggs and milk during pregnancy. As a result, they suffered from iron deficiency anemia and their children were born with a low birth weight. On the contrary, they had poor immunity and were more susceptible to allergies. Unless you are really diagnosed with a certain type of food allergy, there is absolutely no need to blindly restrict food in advance, which will be more detrimental than gain.

If you are really diagnosed with a severe food allergy, carry a first aid card with you, write down your allergens and first aid methods on it, and prepare an epinephrine pen. If something goes wrong, this thing will be more useful than anything else.

After all, the issue of allergic taboos is essentially a "precision job". There is no need to scare yourself into eating anything, and don't be careless and take it seriously. After all, your body is your own. If you pay more attention to it, you can avoid the sin of allergies and you don’t have to suffer from it, right?