What are "trigger foods" in Traditional Chinese Medicine
Anyone with a bit of knowledge about Traditional Chinese Medicine (TCM) is familiar with the term "trigger foods" (发物). It is widely known in folklore and has been highly valued in TCM since ancient times for its relationship with diseases. Trigger foods can be broadly defined as certain foods that, when consumed, are believed to cause the recurrence of old illnesses or the aggravation of new ones. So, what are the trigger foods that TCM often advises against?
The renowned physician Qin Bowei, in his book "TCM's Perspective on the Dietary Issues of Patients," stated: "Foods like shepherd's purse, chives, shiitake mushrooms, and alfalfa, which can cause symptoms such as dry mouth, red eyes, swollen gums, and constipation, are considered to have a 'heating' nature and are commonly known as trigger foods." Dietary restrictions mainly involve avoiding these trigger foods. However, when consulting general TCM books, the term "trigger foods" and its discussion are not found. It is only in texts related to dietetic therapy in Materia Medica that some descriptions of trigger foods can be found. For example: Rapeseed stalks. The "Ming Yi Bie Lu" (Famous Physician's Separate Records) from the Wei-Jin period says: "Eating it in spring can trigger chronic knee diseases." The "Shi Liao Ben Cao" (Materia Medica for Dietetic Therapy) from the Tang dynasty says: "Those who have pre-existing problems with their waist and feet should not eat much of it, as it will aggravate the condition. It also damages yang energy and can sores and oral and dental issues."
Shepherd's purse. The "Shi Liao Ben Cao" from the Tang dynasty says: "Eating it raw can trigger 'Dan Shi' [a type of ailment related to mineral medicines]; do not eat too much of it." Bamboo shoots. The "Ben Shi Shi Yi" (Materia Medica's Additional Records) from the Tang dynasty says: "All bamboo shoots can trigger 'cold blood' and qi stagnation." Houttuynia cordata (fish mint). The "Ming Yi Bie Lu" from the Wei-Jin period says: "Eating too much of it can cause shortness of breath." Eggplant. The "Kai Ben Ben Cao" (Materia Medica of the Kaibao Era) from the Song dynasty says: "Those with long-standing cold conditions should not eat too much of it, as it harms the body and stirs qi, causing sores and chronic diseases." Laver (seaweed). The "Ben Shi Shi Yi" from the Tang dynasty says: "Eating too much can cause abdominal pain, qi stagnation, and vomiting of white foam." Snakehead fish. The "Ben Yan Yi" (Extended Meanings of Materia Medica) from the Song dynasty says: "It can trigger chronic diseases." Grass carp. The "Yan Shu Shu" (Book for Longevity) from the Yuan dynasty says: "It can trigger various sores." Shrimp. The "Shi Jian Ben Cao" (Materia Medica for Food Inspection) from the Ming dynasty says: "It stirs wind-heat; those who are ill should not eat it."
From a modern perspective, the trigger foods circulating in Chinese folklore are quite similar to what medicine calls foods that are prone to causing allergies. Such foods include: milk, eggs, lamb, dog meat; fish, shrimp, crab, clams, mussels, cuttlefish, squid; onions, garlic, chives, mustard greens, cilantro (coriander), celery; chili, pepper, mustard, ginger, alcohol; legumes, raw peanuts, chestnuts, plums, tomatoes, cucumbers, etc. They are respectively foods rich in protein or with a strong smell; aquatic animal products, especially seafood; foods with a special aroma, belonging to traditional meat and fish dishes; pungent and stimulating condiments; legumes and other seed foods, and certain fruits and raw vegetables. These categories largely match the folk definition of "trigger foods." Additionally, foods that are rarely consumed from other regions or foreign countries, as well as genetically modified foods like soybeans and tomatoes, may also trigger illnesses.
The diseases caused by "trigger foods" are basically or mostly related to food allergies (food-induced allergic diseases). It is an adverse reaction triggered by the body's immune regulatory mechanism after an individual ingests a specific food. Its manifestations are diverse and vary from person to person, not necessarily including all allergic symptoms. The most common allergic reactions include oral and lingual numbness and swelling, nausea, vomiting, abdominal pain, bloating, diarrhea, and other gastrointestinal symptoms; skin symptoms such as urticaria, angioedema, eczema, pruritus, and allergic purpura; nervous system and respiratory system symptoms such as migraine, headache, and bronchial asthma.
Although the concept of "trigger foods" is not precisely defined, allergies are well-understood and have gained medical consensus. Therefore, it might be simpler to understand "trigger foods" as foods that are prone to causing allergies. Thus, to avoid the trouble of "trigger foods," you can try the following methods:
Individuals who are allergic to a certain food or have a food allergy should avoid or consume that food with caution.
Once the specific allergenic food is identified, stop eating it. After a period, such as 3-4 weeks, try eating it again. If no allergic symptoms reappear, you can continue to consume that food.
For raw fruits and vegetables that are easily allergenic, you can switch to cooked forms (boiled, steamed, or stir-fried).
For those allergic to milk or meat, the food can be treated with corresponding enzymes (such as trypsin, lactase, trypsin, pepsin) before consumption. For those allergic to cow's milk, goat's milk or mare's milk can be used as substitutes, or condensed milk and milk powder. For those allergic to all dairy products, soy milk can be used as an alternative.
For certain foods that are highly nutritious and need to be eaten frequently, you can start with small amounts. If no symptoms occur, the portion can be gradually increased to the point that it does not cause allergies. After several weeks or months, some people may be able to consume the food in normal quantities.
However, it should be noted that while the body's intolerance to certain foods is different from a food allergy, it has some connection to "trigger foods." For example, when the body lacks lactase in the small intestinal mucosa, the lactose in milk and dairy products cannot be broken down and absorbed in the small intestine, leading to symptoms such as abdominal pain, diarrhea, bloating, and increased gas; intolerance to fava beans caused by a lack of glucose-6-phosphatase, etc.
The "trigger foods" in TCM are difficult to distinguish from certain food allergies in Western medicine. As for foodborne illnesses caused by foods contaminated with bacteria, parasites, toxic and harmful substances, etc., they do not fall under the category of "trigger foods."