More than ten million people around the world are affected by allergies. Flowers in spring, friends' cats and dogs, and dust can cause rashes, sneezing and even uncontrollable itching. Some foods, such as milk, wheat bran, and corn may actually cause human allergies and even endanger lives. So understanding food allergies can not only improve many health conditions, but also help save lives.

What is a food allergy?

Food allergy is an excessive response of the body's immune system to food ingredients or raw materials, usually caused by proteins. The most common food allergens are milk, eggs, peanuts, soybeans, nuts, wheat, fish and crustacean seafood. Of course, there are many other types of food that can also cause allergic reactions in some people, but the above eight categories of food can contain about 90% of the cases.

The symptoms of allergies may vary greatly from person to person. Even if one person has different food, different allergic symptoms may occur. Food allergies vary in severity and speed of occurrence, and may vary at different times. Common acute symptoms include skin discomfort such as urticaria, eczema- gastrointestinal symptoms such as nausea, vomiting, diarrhea- respiratory symptoms such as runny nose, sneezing, shortness of breath, etc.

Severe allergic reactions are uncommon but potentially lethal. Several different systems of the body may simultaneously affect and cause symptoms such as urticaria, laryngeal swelling, dyspnea, hypotension and coma. It may also be a delayed response that produces symptoms such as joint pain, behavioral abnormalities, headache, muscle pain, depression and insomnia.

Food allergy can be divided into immediate and delayed reactions. Immediate allergic reactions are predominantly immunoglobulin E, and usually occur within two hours of exposure to allergens.

Delayed anaphylaxis mainly involves immunoglobulin G, which usually occurs 2-24 hours after exposure to allergens, sometimes even 72 hours later. Because of the long reaction time, it is often impossible for patients to associate the occurrence of symptoms with food. Such allergies usually require a large amount of food allergens, so that the immunoglobulin will not react until it reaches a certain level.

What is a food allergy test?

A blood test can measure your immune system's response to particular foods by measuring the allergy-related antibody known as immunoglobulin E (IgE).

What is food allergy test used for?

Food allergy testing is used to help find out if you or your child has an allergy to a specific food. It is mainly used for people who have had symptoms that could be a food allergy. Testing may also be used to see if allergies have gone away over time.

Food allergy testing can help tell whether you have a true food allergy or a food intolerance or food sensitivity, which may cause similar symptoms. The key difference is that food allergies involve your immune system and can affect your whole body and become life-threatening. But food intolerance and sensitivity don't become life-threatening and generally affect only your digestion.

Examples of food intolerances, or food sensitivities, include lactose intolerance, gluten sensitivity, and irritable bowel syndrome. The symptoms may include belly pain, nausea, gas, and diarrhoea, which can also happen with food allergies.

Traditional food allergy detection mostly focuses on immediate allergic reaction, but most people know to avoid the food causing them immediate allergic reaction because of the rapid and obvious symptoms allergic reaction. On the contrary, delayed allergic reaction is the cause of symptoms involving a wide range of non-specific, so it is difficult to judge which food could cause the allergic reaction for people.

What to expect at NewLife

• Make an appointment with our medical staff.
• Consultation and tests will require 15 minutes.
• You will be notified of results and a consultation will be made to discuss the follow-up measures.