What are Allergies and Sensitivities?

Allergies and sensitivities happen when our immune system become overly reactive to something in our environment. Once stimulated, our immune system initiates a series of reactions within, give rise an array of symptoms.

Common foods like diary, egg, gluten, soy and nuts as well as inhalants like pollens, animal dander and dust mites are the most common allergens.

Types of Food Reactions and their Mediators

Immediate Onset Reactions


Delayed Onset Reactions


Mediators IgE antibodies IgG antibodies
Reaction Within minutes Take hours or days to show up
Symptoms Short reaction time and dramatic symptoms
→ Easy to trace the culprits
Long-lasting and subtle symptoms
→ Hard to trace the offending foods

Who has Sensitivities?

45% of the population are estimated to be suffering from delayed food reaction.1  More than half (54.6%) of all U.S. citizens test positive to at least one allergen. Food allergies affect approximately 6% of young children and nearly 4% of adults in the U.S.2


The Relationship between Food Sensitivities and Health

Yet many food sensitivities are either neglected or untreated, manifest as common chronic symptoms that do not respond to conventional appraoches.

Hidden food reactions burden our immune system, overload defense and reduce repair capacity. Our immune system can become occupied by the reactions unnecessary to take place. This leaves our body more prone to chronic infections and susceptible to chronic, autoimmune or serious lifestyle diseases.


1 Allergy UK
2 American Academy of Allergy, Asthma and Immunology

Symptoms Associated with Food Sensitivities


Eczema, Skin rashes, Urticaria, Dry skin, Psoriasis, Herpetiformis, Hair follicle inflammation


Indigestion, Gas & Bloating, Diarrhea, Mouth sores, Constipation, Cramping pain, Hiccup, Vomiting, Gastroxia


Anxiety, Learning disabilities, Hyperactivity, Autism, Depression, Food cravings, Poor concentration


Joint Pain, Arthritis, Rheumatoid Arthritis, Muscle Aches

Ear & Eyes

Auditory vertigo, Ear effusion, Tinnitus, Itchy eyes


Hypertension, Migraines, Hypotension


Chronic fatigue, Giddiness, Head swelling, Insomnia, Abnormal blood sugar level, Weight fluctuation, Water retention, Obesity, Overweight

Food Allergy? Food Sensitivity? Food Intolerance?

‘Food allergy’, ‘food sensitivity’ and ‘food intolerance’ are often used interchangeably to describe any unpleasant experience after eating the ‘wrong’ foods. It could be very confusing as they share many of the same signs and symptoms.

Food Allergies Food Sensitivities Intolerances
Involve immune system Yes Yes No3
Reaction Immediate
Within minutes
Show up in hours or days
Show up in hours or days
Terms in everyday Classic allergy
Acute allergy
True food allergy
Delayed food allergy
Always get mixed up with allergies and sensitivities Easy to trace the culprits
Symptoms Could look the same4


3 The University of Nebraska-Lincoln
4 The University of Rochester and University of Chicago

Three Approaches to Delayed Sensitivities


Food Sensitivity Test - We care about

YOUR food sensitivities


The latest technologies in laboratory medicine are now able to precisely measure our immune system response to various foods, from small blood samples.

Our test will help you discover with ease what you could continue eating or avoid in your diet to minimize the adverse food reactions and relieve the overloading immune system.

Compare Different Tests in the Market

Test for food reaction can be categorized into two main types: Skin test and blood test.

Skin Test

Inject food proteins onto the skin and observe the redness and itchiness resulted, indicate the immediate (IgE) reaction

Blood Test

Analyze blood for food-specific antibody levels, can indicate both immediate (IgE) and delayed (IgG) reaction


Approved and Reliable Technology that We Trust

We measure IgE and IgG antibodies in your blood, reveal the food reaction that may be responsible for your symptoms.


Our dedicated team of experienced scientists and technicians serve you with the latest technologies:

  • Highly sensitive automated system for IgE testing that tells little biochemical change in your body
  • Fully automated robotic ELISA system for IgG testing, Duplicate runs of each sample for ultimate precision
  • Superior specimen integrity with finger stick whole blood specimens
  • According to an independent Swedish research, HK BioTek employs the ELISA technology with highest accuracy and sensitivity. It is the only test ensuring delivery of consistent and reliable results.

Advantages of our IMMULITE Immunoassay System (in IgE panels):

  • Approved by FDA, is one of the largest automated system available in the market
  • Run on the highly reliable system by Siemens, one of the pioneers in the market
  • Require much less blood for key allergens
  • Much higher sensitivity for detection of more positive results

Implications of measuring total IgE values

IgE antibodies appear as a result of sensitization to allergens, total IgE measures the total quantity of circulating IgE in human serum or plasma samples. An elevated total IgE values indicates that your immunity is weakened (Immune system overload, thus fail to protect cells from functioning). The measurement of total IgE values allows an early detection and diagnosis of allergy and provides an aid in the clinical diagnosis of IgE-mediated allergic disorders.

Effectively assess asthma, allergic rhinitis, urticaria, eczema, allergic diarrhea and other chronic symptoms as excessive IgE values are usually seen in patients suffering from these conditions.

 How to Choose a Reliable Testing Service Provider?

According to Dr. Nina Pierpont (2009), a Doctor of Medical Science, a real gold standard of science should be involved both carefully observation and precise measurement, resulted in having same result after all; in other words – REPRODUCIBILITY. This means a sample is tested repeatedly, with its result validated for the highest accuracy.1

When choosing a test, you should enquire the laboratory about the reproducibility of the test you are going to take, so that you will know how consistent and reliable the test result is.

1 Byrd, D. et al., 2000


AFC process

Testing at Clinics

Our service is carried by 450+ healthcare professionals in Hong Kong and Macau. Our staff could refer you to practitioners that suit you, according to the location, nature of practice and your insurance coverage.

  • Western medicine physicians (General Practice, Paediatric, Dermatology, ENT, etc)
  • Chinese Medicine Practitioners
  • Dietitians or Nutritionists
  • Naturopath or other holistic practitioners

If you wish to take the test with your family doctor, please let us know your name and the name of your doctors. We will contact them for you and make our test available to you at your greatest convenience.

Our email: info@hkbiotek.com and our contact number: +852 2763 1488.


Food Sensitivities Testing in Macau

We have a number of specialists in Macau carrying our service in Macau. Please feel free to contact us for referral and further information.

extensive test items

categories of test items

Food panels: For Delayed (IgG) or Immediate (IgE) reaction

112 Asian Foods (IgG)

Common Asian fruits, vegetables and spices

96 General Foods (IgG)

A variety of dairy products and cereals

96 Vegetarian Foods (IgG)

Cover a wider variety of grains and legumes

19 Foods (IgE)

Covers  the eight key food allergens

20 Inhalants (IgE)

Focus on Immediate reaction; Cover Trees, Grasses, Weeds and indoor allergens such as dust mites, cat and dog dander

16 Inhalants (IgG)

Focus on Delayed reaction; Include three major type of allergens: grass, mold and indoor allergens

15 Molds (IgE)

Focus on Immediate reaction; Covers common mold allergens found in human, plants, soil, food, indoor and outdoor



Insomnia & Fatigue

Angela (28 year old)
“Thanks to HK BioTek. I now find myself free of the persistent fatigue and bouts of insomnia. At that time, I was studying my master degree and having a stressful job. I felt exhausted but couldn’t sleep at night. Had a number of tests ordered through my GP, but still clueless on what was happening. I really didn’t think this could happen on me when I was still under 30. These in fact turned out to be a problem with diary, egg and cherry. After a slight change in diet for 1 month, I felt the energy has come back and I am better than I was.”


Timothy (9 years old)
“Timothy suffered from Attention deficit hyperactivity disorder (ADHD) when he was just nine. The report of the test indicated that he was highly allergic towards daily products, egg, gluten and many fruits. We therefore follow the diet plan and the effect was almost instant. He has become much calmer, his temper improves a lot and so did his school work. I know several of parents having kids with autism/ADHD problem have had the tests done as well and their response was the same.”
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Jamie (4 years old)
“My kid suffered from asthma since she was four. Followed up by several famous specialists in the town, her situation had not got better. I didn’t want to put her on inhalers or medicine for the rest of her life. I bought her to a clinic carrying HK BioTek’s IgG test. The report showed that she was immensely allergic to a variety of foods. We were not surprised and started avoiding the reactive food for her as advised by the nutritionist. After avoiding the reactive foods for 3 months, her condition was getting relatively stable. My family was very blessed to find the way to manage asthma, but will still watch Jamie’s diet very carefully.”

Chronic Diarrhea & Bloating

Chris (30 years old)
“On a daily basis, I would have bloating and diarrhea. It could be quite severe sometimes. Plus I was generally quite irritable due to the discomfort of my stomach. I did sought help from many doctors and went through many checkups. One of my doctor friends suggested me to try to test for food sensitivities that worked for himself in other symptoms. My results revealed that I was highly reactive to egg white and gluten. My symptoms improved significantly after 2 weeks. I am quite sure my problem are caused by these foods because when I ate them accidentally, the symptoms will most likely come back in the next one to 2 days.”

Chronic Infections

Lok (4 years old)
“Since Lok was 2 years old, he started having frequent episodes of various illnesses including viral fever, gastroenteritis, conjunctivitis, and rhinitis, recurrent attacks of bronchitis, urticaria and constipation. His father and me also felt weird about this because Lok used to be quite healthy. Until we took part in a health talk and talked with the doctor, he suggested that Lok should take an IgG test and the result showed that he is severely allergic to dairy products and soy. After removing these offending foods from his diet, Lok has gradually regained his health. As time passed by, he has become much stronger now”


Chloe (17 years old)
“I have to say that I was a little skeptical when firstly knew after this test. I have battled with eczema since I was few months old, tried almost every treatment available. The experience from all these years makes me feel that having dry, itchy and sensitive skin may be part of my personality. I was then found to be positive to some common foods. I saw an almost instant improvement in my symptoms.
I have already forgot why I would get myself tested, but it is definitely bliss to be symptom free, and I have never imagined this would work for my skin.”

Chronic Cough & Runny Nose in the morning

Helen (48 years old)
“I came for testing after suffering with a tickly cough which both many doctors and I have been unable to find a cause for. This test was a bit of a last ditch attempt for the cause. My result came back to show I have a strong reaction to dairy, shrimp, corn and sesame. I was also moderately reactive to egg white. By following the customized rotation diet, the symptom improved dramatically. Surprisingly, I used to sneeze a lot after waking up, now it’s almost gone.”



1. What are the strengths of our AFC test?

  • Highly sensitive automated system for IgE testing that tells little biochemical change in your body and fully robotic ELISA system for IgG testing
  • Comprehensive test items
  • Only few drops of blood for delayed onset test
  • Beautifully executed with reliable technologies and lab for ultimate precision
  • Customized rotational diet plan go along with report

2. Could we know more about the specificity and accuracy of the Aller Food Check test ?

Our AFC test utilizes fully automated robotic systems for ELISA and Enzyme-amplified Chemiluminescence assay. It undergoes stringent biochemical process detect antibodies in the blood, which interprets your immune system’s response to food. Our test gives you the assurance of quality and reliability as all tests are completed under US BioTek Laboratories’ facilities. Each sample is run twice to ensure consistent results. Our laboratory is an independent clinical laboratory approved by CLIA (US Clinical Laboratory Improvement Amendments) accredited by COLA (US Commission on Office Laboratory Accreditation). The laboratory is also licensed by the State of Washington for performing testing worldwide.

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3. How can you ensure the blood collected in the strips will not be contaminated during transit?

The blood strip will be air dried for 45 minutes in room temperature before sending out. A dried blood sample provides no medium for bacteria to attack. Using our blood strips is a proprietary method proven to ensure the blood sample to be stable for at least 3 weeks under room temperature.

Comparison studies have been done to prove that results from blood strips and serum showed no discrepancy. Therefore, sampling with strips are as effective as obtaining serum from blood drawing.

4. Why are only 19 foods covered in the IgE food panel?

According to US FDA, the eight most common allergenic foods are Milk, Eggs, Fish (e.g., cod), Crustacean shellfish (e.g., shrimp), Tree nuts (e.g., almonds), Peanuts, Wheat and Soybeans. These foods account for 90% of food allergic reactions, and are the food sources from which many other ingredients are derived. To provide a more extensive test range, in addition to these 8 foods, our IgE food panel also covers other common offending foods.

Finding positive results for IgE is often difficult as blood IgE levels are present with a short half-life of two days. Yet, this proven, reliable and accurate IMMULITE assay system brings greater specificity for detection of more positive results.

5. Why measuring total IgE values?

  • IgE antibodies appear as a result of sensitization to allergens, and the measurement of circulating total IgE values provides an aid in the clinical diagnosis of IgE-mediated allergic disorders
  • Allow an early detection and diagnosis of allergy. Total IgE measures the total quantity of circulating IgE in human serum or plasma samples. An elevated total IgE values indicates that your immune system is weakened.
  • Effectively assess asthma, allergic rhinitis, urticaria, eczema, allergic diarrhea and other chronic symptoms as elevated levels of total IgE are usually seen in patients suffering from these conditions.

6. What’s special about the Mold Panel (IgE)?

Susceptible populations of airborne allergies is huge and mold spores are one of the most common causes of airborne allergy. Molds are fond of warm and moist environment. Due to the warm and humid climate of Hong Kong, Taiwan and Southern China, traces of molds are seen almost all seasons. Many of us have found mold on walls, bathrooms, gap between tiles, furniture, and even leather shoes. Just think about how much molds we are living in and how much we have inhaled without even knowing it?

Asthma, other respiratory conditions, or weakened immune systems are usually signs of mold allergy or exposure. Covering common mold allergens found in human, plants, soil, food, indoor and outdoor, this is an ideal allergy test for you to minimize the risk of mold exposure by identifying your mold allergens.

7. What should I do if I want to take the test at a clinic?

More than 400 healthcare professionals in Hong Kong and Macau provide our testing services, including pediatrician, dermatologist and so on. In addition to IgG antibody test, we also provide IgE antibodies test. Doctors are equipped with extensive medical knowledge and clinical experience, we also provide these healthcare professionals with comprehensive nutrition resources and training to join hands to help patients to get rid of allergens while maintaining nutritional balance. Please let us know your preference or let us contact your family doctor, so that you could take the test with a doctor you are familiar with.


1. How do I go about the AFC testing?

You could:

  • Make an appointment for blood sampling at our office or our sampling outlets all over Hong Kong;
  • Purchase the test kit from us, collect the blood sample on your own, then return it back to us;
  • Do it at the clinic of your family doctor or doctors carrying our tests

Our Office Hour: 10am-7pm (Mon-Fri); 9am-5pm (Sat); Closed on Sun & Public Holidays

It will take 10 – 20 days to get your report ready.

2. How much blood is needed for the food antibodies test?

For testing the delayed onset reaction, only few drops of blood is needed. For the immediate onset reaction, you will be arranged to undergo a blood drawing at a lab in your preferred location. The exact amount of blood needed depends on the type of test you enrolled.



1. Should I be fasting before my blood sampling ?

No fasting is required. This test is a semi-quantitative analysis of the antibodies in our body, and it is produced while the foods being taken prior to the test.

2. Is the AFC test suitable for all ages ?

Adults and children can take the test. In general, infant after 6 months starts to produce its own antibodies. Thus, kids age after 6 months and start eating solid foods can take the test.

3. Should I take the test if I am pregnant ?

One of the reasons for developing adverse food reaction is genetic predisposition. If a pregnant lady is allergic to some foods and wasn’t aware of it, the IgG and IgE antibodies produced would transfer to the baby. Medical professionals have suggested that pregnant women could consider testing when necessary so as to prevent baby from allergies and sensitivities.

4. Should I be eating differently before taking this test?

Any test for IgG is able to reflect your diet in past three months while that of IgE reveals your reaction in 48 hours. The beauty of the test is to tell whether the foods you eat may make your sick, therefore we recommend test clients to eat normally prior to testing, only this way, the test can reveal more information from your way of eating.

However, some of the test clients may consider to consume foods that they seldom eat before taking our test. You could choose to do this, and we recommend you to consume these foods at least for a week before enrolling to our test. This will greatly enhance the chance of detecting those “reactive” foods. However, if you have history of anaphylaxis or severe allergic reaction, you should avoid eating these foods as second exposure can prove fatal. Please consult your physician if you have any questions concerning this test.

5. Can I have this test done if I am taking Chinese or Western medicine?

In general, the major concern is steroidal drugs, e.g. cortisone, because it can suppress the immune system, and thus may reduce the antibodies present, causing a “false negative” report. Thus it is advisable to stop taking the steroidal drug for at least 3 weeks before taking the test. Tropical steroid is not part of the concerns.

6. Do I need a doctor’s prescription to have the AFC test done?

Any individual can order any tests as his or her health information but not for diagnosis. A doctor’s prescription is not required.



1. What information does the report provide?

Aller-Food Check result will be shown in bar charts, according the food categories. The classes of 0 to VI denotes the level of antibodies detected through detected through ELISA or Enzyme-amplified Chemiluminescence assay.

For IgG and IgA:

– Abstain from the reactive foods based on the allergic level.
– Rotate the foods that are in the low or no-reaction category.
Level O: Foods in this column can be eaten freely.
Level I to II: Low amount of antibodies are present against specific food. For the first 3-month you may rotate these foods every 7 days, then rotate these foods every 4 days afterwards.
Level III: Moderate amount of antibodies are present against these specific foods. You should avoid these foods for a 3-month period, and rotate these foods every 4 days afterwards.
Level IV to VI: There are elevated antibodies in the body against these specific foods. You should avoid these foods for at least 6-9 months, depending on your health conditions, and re-introduce carefully later.

For IgE:

Items with positive results should be avoided in your lifetime.

The reports will come with a rotational diet guideline and a wallet card lists out the reactive foods (when there is any result greater than level III), as well as information sheets and rotational diet booklets for you to make good use of the test result.

2. How do we go about report interpretation ?

You will receive the test result via email and be interpreted by our Nutrition consultants via phone or face-to-face consultation. Hard copies of the report as well as other supporting material will be handed to you during consultation or posted to you. You can always reach our customer hotline (852) 2763 1488 when necessary.

3. I am found to be IgG positive to cow’s milk and egg. Would I be nutritionally deficient if I completely avoid these protein rich foods?

You may follow the customized rotation diet reference to avoid the offending foods. Remember that there are always substitutes for most of the offending foods. For example, if you are allergic to cow’s milk, most nutritionists will suggest soy milk, rice milk or almond milk to be the best available alternatives, and you can obtain calcium and protein from other food sources as well.

4. Should I retest?

You will have a 6 to 9 month of food elimination process after identifying your offending foods. A follow up test would be necessary if you would like to reconfirm whether you are still reactive to the offending foods, and a retest would also be able to identify if you may experience new offending items when you are in the process of elimination.

5. How long does it take to improve my symptoms after the test ?

In most cases, if your condition is due to allergies or sensitivities to food or inhalant, you should notice improvement of your symptoms in a couple of weeks of avoidance.

If your symptoms persist, you should consider other factors could play a role in affecting your current health conditions. After all, avoiding offending foods is one of the factors that you could start with or control, but it is not the magic bullet for all health issues.

6. Can the test result of IgE indirectly reveal body’s IgG reactions?

No. We have two separate pathways and mechanisms for IgE and IgG reactions. Even though people may observe the same or similar symptoms for IgG and IgE reactions, they are not necessarily related. Based on our observations, test clients often display different IgG and IgE reactions towards the same food. If you have difficulties in choosing the right test, you should consult your practitioners’ advice by taking reference of your own medical history. HK BioTek’s food antibodies tests cover IgE, IgG and IgA to meet your clinical needs. You are always welcome to contact us.

7. As revealed by some online articles, testing for IgG will lead to death?

Special attention should be paid to the potential misunderstanding between IgG and IgE. IgG and IgE works differently and it is not sensible to assume the same reaction apply to one and another. Some people may perceive that testing for IgG might potentially lead to death. In fact, there are several major methods to test for allergies or sensitivities. Blood test, one of the available methods, is deemed to be the least risky in nature (unless the patients are having clotting problems, or having unpleasant past experience in blood drawing). Sparse cases of death related to skin prick test were recorded in the USA in 1990-2001 [1]. The first death related to Oral Food Challenge in the USA was reported in August, 2017 [2]. Up till now, no fatal cases related to IgG testing are reported.

[1] Bernstein D., Wanner M, Borish L, Liss GM., 2004. Twelve-year survey of fatal reactions to allergen injections and skin testing: 1990-2001. J Allergy Clin Immunol., 113:6, pp. 1129-36. Retrieved from: https://www.ncbi.nlm.nih.gov/pubmed/15208595

[2] Allergists Respond to Death of 3 year-old Boy During Oral Food Challenge. American College of Allergy, Asthma & Immunology; American Academy of Allergy, Asthma & Immunology; and the Canadian Society of Allergy and Clinical Immunology. 2017. Retrieved from: http://acaai.org/allergists-respond-death-3-year-old-boy-during-oral-food-challenge

8. Does IgG antibody only reflect the food I eat? And the more I eat, the more reactive I am towards that food?

Your body does not react to a certain kind of food, but if you eat too often, the body may not be able to handle too much of a food, your immune system will produce IgG antibodies against this food gradually. Theoretically, to know your results towards certain food, you need to consume the food first. In fact, any blood tests (no matter IgG/ IgE) require the test clients to be exposed to allergens. Common allergens of IgG antibody test are egg, dairy and gluten, since they are frequent food in our daily diets, people may perceive that the more I eat, the more reactive I am towards that food, and the IgG results only reflect what food are included in my diet. However, rice, pork and other food are common in Asian diet, it’s rarely seen that test clients are reactive to these food. We can tell that, eating frequency is not the only factor in causing food sensitivity.