How to write a food diary: help you identify real allergens

The core logic of relying on food diaries to find allergens is to accurately anchor the correspondence between "full information on food intake - body reactions". If you miss any link, you may find the wrong culprit, and your work will be in vain for several months. In fact, keeping a food diary is like being a detective for yourself. Every bite you take is a suspect, and your body's reaction is the crime scene. Only by recording all the clues can you find the real culprit. Otherwise, if you miss the key clues, you will only regard innocent milk and eggs as scapegoats, and you will be abstaining from food for a long time.

I met a girl who suffered from recurring urticaria for half a year. I kept track of it for two months at the beginning. Every time she got the rash, she only listed the "serious meals" she ate that day, such as rice, vegetables, and milk. In the end, she thought she was allergic to milk and stopped eating fresh milk and yogurt. However, the rash still popped up every now and then. Later, when I helped her go through the records, I discovered that she didn’t remember the dried mango she bought every time she got off work, or the American drink she often drank in the office that she sprinkled with cinnamon powder. These two were her real allergens.

Many people also think that food diaries are useless, and it is better to go to the hospital for allergen testing and be sure. This is actually only half right. For those kinds of immediate acute allergies that make you out of breath and develop large wheals half an hour after eating, you should definitely go to the hospital for an IgE test. Don't risk yourself by trying blindly. However, for many chronic, delayed-onset allergies or food intolerances, the false positive and false negative rates of the test are not low. I have seen many people whose test reports show that they are not allergic to eggs, but they get headaches and diarrhea when they eat soft-boiled eggs. Only a continuous food diary can figure out this long time difference.

If you really want to remember, it doesn’t have to be complicated at all. You don’t need to buy a special notebook. You can do it with a mobile phone memo. You don’t even need to type the names of the ingredients word for word. You can just take a photo and put a time stamp before eating. If you feel any discomfort within 48 hours after eating, whether it is a few small rashes, inexplicable flatulence and acid reflux, a sudden stuffy nose, or even insomnia and fatigue for no reason, just apply it at the corresponding time point. Don’t miss out on those things that you think are “not worth mentioning”, such as the spices in stir-fries, free pickled radishes in takeaways, half a piece of chocolate stuffed by colleagues, and even the additives in the sparkling water that many people have been looking for for more than half a year. In fact, it is these inconspicuous gadgets.

Of course, some people say that sometimes you eat more than a dozen ingredients in one meal, and you can’t tell which ones are allergenic. In this case, you can do a simple elimination provocation test: first stop all the suspicious ingredients in your records for 2-4 weeks. After the body’s allergic reaction has completely subsided, slowly add them back again. After each addition, observe for about 3 days. If the previous symptoms of discomfort appear immediately after adding them, it is basically locked. The girl I just mentioned tried this. After she stopped using dried mango and cinnamon, her rash disappeared in half a month. Later, when she tried cinnamon alone, she got two small red envelopes on the same day. She finally found the culprit and no longer had to blame milk.

Oh, by the way, a reminder, if you have a severe immediate allergy, do not do a provocation test at home. If you accidentally touch highly allergenic food and go into anaphylactic shock, you will be in trouble. In this case, you must conduct an investigation under the guidance of a doctor.