Food Allergy


Q1. What is food allergy?
Food allergies occur when the immune system attacks a food protein by mistake. If you are allergic to a particular food, a very small amount is enough to cause allergic reaction and related discomfort. Allergic reaction can happen within two hours, or even a few minutes.

Q2. What are the symptoms of food allergy?
Symptoms of food allergy are varied. Some people may suffer from watery eyes, running nose, while some may have abdominal pain, stomach ache or even vomit. Serious symptoms include hives all over the body, or difficulty in breathing. It can be life-threatening under extremely severe circumstances.  

Q3. What are the common food allergens?
Most food allergies are caused by eight types of food. We usually tell our patients that four of them are introduced to children when they start consuming solid food, namely milk, eggs, soy and wheat. The other four are commonly known allergens, which include peanuts, tree nuts such as almonds, cashews etc., shellfish such as shrimps and crabs, as well as fish.   

Q4. I always suffer from diarrhoea after drinking cow milk. Am I allergic to it?
Many people suffer from abdominal pain or stomach upset after drinking cow milk. Rather than allergic to cow milk protein, most of them are simply lactose intolerant. Lactose intolerance occurs when the body cannot efficiently digest lactose and cause abdominal upset. Here the immune system does not attack a food protein by mistake, and you are not allergic to protein in cow milk. People with lactose intolerance can often drink a small amount of cow milk from time to time without discomfort. They can also consume a small amount of butter or milk tea, but not a whole glass of cow milk.   

Q5. What is the difference between food allergy and food intolerance?
Food allergies occur when the immune system attacks a food protein by mistake. It’s more like picking a wrong opponent.  Food allergies are characterised by three things: first, a small amount of a particular food is enough to cause discomfort. Second, the discomfort repeats every time you eat the same food. Third, you may start to feel uncomfortable as soon as the food is consumed, usually within 2 hours or even a few minutes.

Reactions of food intolerance are random. Most cases are intolerant not to food protein, but to lactose or histamine. Some people suffer from fructose intolerance only if they eat a large amount of fruits.  If the reactions occur occasionally, it usually has to do with food intolerance.

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