14 food allergens

The 14-item food allergen screening commonly used in domestic clinical practice covers more than 90% of common allergenic foods in the daily diet, including wheat, peanuts, soybeans, milk, eggs (containing protein and yolk), common marine fish (cod, salmon, etc.), shrimp, crab, shellfish, common tree nuts (cashews, walnuts, almonds, etc.), mango, peach, pineapple, beef and mutton. It is currently the best preliminary screening combination based on comprehensive coverage, testing costs, and epidemiological data.

A while ago, I accompanied my best friend with allergies to get a report. She stared at the two plus signs in the milk category for five minutes and said that she had never had diarrhea after drinking iced milk for more than 20 years. At most, she only had a little flatulence occasionally. How could she be labeled as having a "milk allergy"? In fact, this is also the first reaction of many people after receiving the 14-item screening report. They either feel that it is completely inaccurate, or they are so frightened that they blacklist all the positive foods and dare not even touch them.

I worked in the allergy department of a tertiary hospital for half a year before and saw too many similar situations. There was a little boy who was in the second grade of junior high school. He coughed repeatedly for more than half a year. All lung smears and laryngoscopes were checked and nothing was wrong. Finally, he did 14 allergen screenings and found that wheat, eggs, and milk were all strongly positive for wheat, eggs, and milk. This was a variant asthma caused by allergies. Within three months of strict dietary restrictions, the coughing problem basically stopped recurring. But there are also counterexamples. An aunt in her sixties was found to be positive for shrimp. She was extremely anxious and said that she had eaten shrimp all her life and had never had an itch. Later, she did an oral food challenge test and the result was completely fine. However, during that time, she had influenza and her immunity was low, and her total serum IgE level was high, which resulted in a false positive result.

When it comes to the selection criteria for the 14 items, they are actually not determined based on the epidemiological statistics of domestic allergic diseases in the past ten years. The sensitization proportion of these 14 types of food exceeds 90% of all food allergy cases, and it is sufficient for the general population to conduct preliminary screening. Of course, there are different voices. Many private medical examination institutions will now expand food allergen screening to 20 or even 30 items, adding foods that have only become popular in recent years, such as avocado, chia seeds, and kiwi fruit. Doctor friends there also have their own reasons: Nowadays, people’s diet is becoming more and more complex, and niche foods that were rarely eaten in the past have now become a daily routine for many people. Allergy cases are increasing every year. For young people who often eat light foods and frequently try new things, it is not unnecessary to add appropriate items.

Oh, by the way, there is also a very common controversy: should foods tested positive be completely tabooed? The traditional idea of ​​​​allergy intervention is to strictly avoid as long as the indicator is positive, especially for people with clear allergic symptoms, to avoid inducing severe allergic reactions. However, clinical research in the past few years has also raised new possibilities. If IgE is only slightly elevated and there are no discomforts such as rash, itching, diarrhea, or difficulty breathing when eating the corresponding food, you can try to introduce it gradually in small doses and slowly build up tolerance. Many children are diagnosed with milk and egg allergies when they were young, and they can eat normally when they grow up.

To be honest, there is really no need to regard the results of these 14 screening tests as an imperial edict. I once met a girl who developed hives all over her body after eating fresh spring bamboo shoots. All 14 tests were negative. This is because spring bamboo shoots are not on the low-allergenic list of routine screening. If you clearly have an uncomfortable reaction after eating something, even if the screening results are all negative, you have to avoid it. After all, your body's reaction is the most accurate.

If you are really unsure about whether you should avoid foods with a positive result, just do an oral food challenge test. That is the current gold standard for diagnosing food allergy, and it is much more reliable than looking at the 14-item screening results alone. To put it bluntly, this 14-item screening is a tool to help you narrow down the scope of investigation. Don’t panic too much, and don’t take it completely seriously. Adjusting it based on your actual dietary response is better than anything else.