Some time ago, an American posted an interesting story on social media that his daughter was severely allergic to peanuts in the United States, and after coming to China, not only was she no longer allergic to peanuts, but she was no longer allergic to all the foods she was allergic to before.
Image source: Weibo ID: Emperor Bar Official WeChat
Many netizens also shared similar experiences, foods that are not allergic in China will be allergic to them after eating them abroad. Some netizens reported that they are allergic to seafood when they eat it in China, but they can't eat seafood in Australia.
Image credit: Zhihu
Why is there such a big difference in the consumption of the same food in different countries? Let's explore it today.
What determines allergies?
To understand this question, we must first understand what determines allergies. Allergies are allergic reactions caused by antigens and antibodies, and allergies can be easily caused by contact or consumption of allergens. Allergies can be divided into skin allergies, respiratory allergies, digestive allergies, etc.
Skin allergies can manifest as erythema, wheals, blisters, itching; Respiratory allergies can manifest as coughing, sneezing, runny nose, asthma, dyspnea; Gastrointestinal allergies can manifest as abdominal pain, diarrhea, and bloating.
Everyone's allergens are different, and the severity of allergy symptoms is different.
Why do allergies go away all of a sudden?
As mentioned at the beginning of this article, it's not uncommon for the same person to react differently to the same allergen in different regions. The main reasons are as follows.
Cooking:
Different countries or regions have different cooking methods, and some unique cooking methods may change the allergens in the food, thereby reducing the occurrence of allergic reactions.
Less cross-contact
At present, more than 1,000 allergens have been detected in humans, but the actual allergens in nature far exceed this number. Some allergic reactions are not caused by a single allergen, but are triggered by cross-stimulation of multiple allergens.
In a new environment, if there is less cross-contact with allergens, it will not cause an allergic reaction. When you change to the original environment and the allergen cross-contact occurs again, allergies will occur again.
Altered intestinal flora
Changes in the living environment and diet may affect the gut microbiota, which in turn affects the immune system, which may reduce allergy symptoms to some extent.
Regional differences
Taking food allergies as an example, there will be some differences in the composition of food in different regions due to different climates, soil composition, chemical fertilizers and pesticides, storage and transportation methods, cooking methods, etc. If the content of the allergen happens to be different, different sensitization conditions will occur.
Allergies are a dynamic process
Allergy is a dynamic process, and when we usually say allergies to peanuts, crabs, milk, etc., we are not allergic to all the components of these foods, but to their single components.
Therefore, it cannot be understood that an allergy to peanuts is an allergy to all peanuts, and when a certain type of peanut contains little or no allergenic ingredients, it will not cause allergies. Changes in the internal environment of the human body also have an impact on allergies, so the presence or absence of allergies cannot be understood mechanically.
We can summarize some of the experiences we have when allergies do not occur and then reduce the occurrence of allergies as much as possible.