Allergies, Food Intolerance or Just a Bit Sensitive?

Know the difference between allergies, food intolerances & sensitivities, and learn about the best ways to treat your condition.

In Australia, about 2% of all adults (more than 1 million people) suffer from some form of food allergy. Food intolerances are more common, affecting up to 25% of all adults and food sensitivities might be even more common, but no official statistics are at hand.

What are the main differences between these problems? In many cases, it is hard to tell, because many of the symptoms are similar.


Food allergies


According to statistics from the Australasian Society of Clinical Immunology and Allergy, food allergies occur in about 10% of infants, up to 8% of children, and in about 2% of adults from Australia and New Zealand.


  • What are allergies?


Allergy is a reaction from our immune system against a foreign yet innocuous substance, known as the allergen. Allergens can be defined as normally harmless substances that, for some reason, cause an immune response in our body, resulting in an allergic reaction.

Common allergens include pollen, mould, dust mites, certain foods or insect venom (like when mozzies bite you). In terms of food, some common allergens include nuts, milk, eggs, shellfish, wheat (gluten), soybean, and fish.

Focus on Gluten: Wheat is a natural source of gluten, a named used to depict two groups of proteins, called prolamins and glutelins. These proteins are common allergens: a lot of people in Australia and other countries are allergic to gluten.

A common affliction involving gluten is Coeliac disease, an autoimmune disorder affecting nearly 3.5 million Australians (1 in 70). People with this condition have a genetic condition that drives their immune system to attack gluten proteins as if they were an invading pathogen. As a consequence, cells in the small intestine get damaged, causing gastrointestinal problems.


  • Typical allergy symptoms


In general, allergic reactions can cause a wide range of symptoms, with varying intensity. People with mild allergic reaction can experience:

  • Swelling of the face, lips or eyes.
  • Hives, also known as urticaria, on the skin
  • Abdominal pain
  • Vomiting

People with stronger allergic reactions can experience more serious symptoms, in addition to the symptoms above, including:

  • Difficulties to breath
  • Swelling of the tongue or throat
  • Dizziness or losing consciousness
  • Heartbeat alterations
  • Diarrhea
  • Chronic cough

If a severe allergic reaction is left unattended, it can develop into a potentially fatal condition known as anaphylaxis. This is a severe systemic immune reaction that can cause life-threatening problems with your breathing and circulation1.


  • How do allergies form?


There are two steps in the process of developing an allergy: sensitisation and re-exposure.

  • The first step, sensitisation, occurs when your body meets an allergen for the first time. Here, specific immune cells recognise the substance as a potential threat. From this point forward, a chain of events unfolds, involving other immune cells (like T and B cells) that result in the production of antibodies specific to the allergen. These antibodies will bind to specific immune cells (like mast cells), which help the body recognise that specific allergen in the future2.
  • The second step involves re-exposure to the allergen and development of the allergic reaction. Once the allergen enters the body for a second time, your immune system will recognise it, thanks to the antibodies it created before, and will mount an attack2.


But, why does the immune system identify something like pollen or milk as a pathogen in the first place? The short answer is genetics. People with allergies have certain genetic predisposition (specific genetic mutations) that cause the immune system to recognise a specific substance as a foreign and dangerous particle3.

The gut microbiota is another factor to consider when trying to understand allergies. Studies have linked gut microbial composition in infants with their likelihood of developing allergies as adults4-5. In adults, studies have established links between the presence/absence of specific gut bacteria with immune function, and with the development of allergies6-8.


Can you “grow out” of food reactions?


Sometimes you can, especially children, but it is not clearly understood why. For example, children who develop allergic reactions to wheat, eggs, cow’s milk often manage to leave their allergies behind as they grow. However, other types of allergies, such as shellfish or nut allergies tend to persist into adulthood9.

Food allergies, however, are not the only food-related problem people can experience. Food intolerance is another even more common problem, affecting both adults and children.


Food intolerance

Food intolerance is the inability to digest particular foods and it is different from food allergies.


  • What is food intolerance?

People suffering from a food intolerance basically do not have the biological mechanisms needed to process certain foods. Food intolerance can also occur due to chemicals present in the food, either natural or artificial, which react adversely with the biochemistry of our body.

A classic example of a food intolerance is lactose intolerance. People who are lactose intolerant are unable to effectively digest lactose, the key form of sugar found in milk. At the heart of their intolerance are genetic mutations that cause the malfunction of a gene called LCT, which is responsible for the formation of the enzyme lactase, involved with lactose digestion10.

  • Typical symptoms

People who suffer from food intolerance can suffer from stomach pain, bloating, flatulence, diarrhoea, irritable bowel syndrome (IBS), rashes, or hives (urticaria), among other symptoms. Many of these symptoms are similar to those reported for food allergies, so it is important to consult a health practitioner before reaching a conclusion about your condition.


What are the most common food intolerances?


Food intolerance is a common malady, and there is a wide range of food products associated with this condition. Some common food components known to cause intolerance include:

  • Gluten, specific proteins found in wheat.
  • Lactose, present in all milk-based products.
  • Vasoactive amines, which are present in pineapples, bananas, baked meat, vegetables, red wine, wood-matured white wine, avocados, chocolate, citrus fruits and mature cheese.
  • Salicylates, natural aspirin-like compounds present in herbs and spices like curry powder, paprika, thyme, garam masala, aniseed (anise), and rosemary. Fruit and vegetables like cucumbers, olives, sweet potatoes, berries, pineapple, cheery and apricots also contain high levels of salicylates.
  • Monosodium glutamate (MSG), naturally found in camembert cheese, Parmesan cheese, tomatoes, soy sauce and mushrooms, among others. Artificial MSG is also commonly used as a flavour enhancer on some foods.


Finally, another form of adverse food reaction is called food sensitivity, which encompasses a milder reaction to certain foods. Symptoms can include digestive problems like bloating or abdominal pain. However, currently, there is not enough information about how common this condition is in Australia or how to differentiate it from food intolerance.


Testing your food reactions


The first and most important step to treat food allergies or any adverse reactions to food involves comprehensive and accurate testing.

At the Australian Centre for Functional Medicine, we employ state of the art immunological-based testing, relying on the identification of antibodies from different food products that are common allergens, such as gluten proteins, eggs, cow milk, corn, rice, and many other foods. Our testing technology is unique: we are the only clinic in Australia offering this advanced testing technology.

If your body has developed an allergy to any food products, our tests will be able to detect the specific food products that are causing you trouble.


Virtual Example


Imagine you have been diagnosed with coeliac disease and you are following a gluten-free diet. Yet, you experience recurrent health problems, like fatigue, skin rashes, sores, pain in the joints, or a weak immune system, reflected by constantly getting a cold and feeling weak. Such symptoms could be due to undiagnosed allergic reactions to other allergens.

With our “Array 4” test (Gluten-Associated Cross-Reactive Foods and Foods Sensitivity), we can identify food items that might be cross-reacting with your gluten allergy. This test can confirm the presence of antibodies against food products like cow’s milk, whey protein, milk chocolate, and many others. Furthermore, testing for the composition of your gut microbiome would reveal evidence of gut dysbiosis, which is another factor that may influence these symptoms.

If our test confirms the presence of antibodies against milk, whey protein or any other food product or if we encounter evidence of gut dysbiosis, this will help us identify the underlying causes of your symptoms. Treatment for these problems would involve changing to a new diet as well as improving your gut microbiota through the use of probiotics, diet and other lifestyle changes.




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