Food allergies and intolerances … what’s the difference?


Food allergies and intolerances are incredibly common and it’s likely that you have friends, colleagues, or family members with an allergy or an intolerance. Food allergies are rising in industrialised countries with Australia having one of the highest allergy rates in the world. Similarly, food intolerances are growing with up to one-quarter of the Australian population believing that they have a food intolerance. Whilst both food allergies and intolerances share some similar symptoms, there are important differences between the two, so let’s explore those differences and learn more.


Allergies are an overreaction of the body’s immune system to a protein. The protein can come from food, pollen, animal fur, dander, dust, mould or many other sources.  An allergy is a response from the immune system which attacks a harmless substance such as food, pollen, or dust as if it were toxic. In response, the immune system releases large amounts of chemicals that can affect the skin, heart, breathing and gastrointestinal tract. These chemicals include histamine which can cause a loss of blood pressure, wheezing and itching. This allergic response can become life-threatening, especially if it results in anaphylaxis. Anaphylaxis is a medical emergency. Common food triggers of this severe allergic reaction are nuts, eggs, milk, wheat, and seafood.


An intolerance is a chemical response rather than an immune response. Being food intolerant is not the same as being allergic and you can often tell the difference between an allergy and intolerance by the time it takes the body to elicit a reaction. Usually, an allergy would illicit a response very quickly after contact with the allergen. In contrast a food intolerance can take anywhere from 12-24 hours to show up. An intolerance is slower to present symptoms and those symptoms whilst uncomfortable, are usually non-life-threatening, such as headaches, bloating, nausea, wind, ulcers and hives.


If you have a food allergy or are cooking for someone with an allergy it is important to know the terms used to describe these foods on food labels. For example, soy can be listed as soybeans, soy protein isolate, soy lecithin, or hydrolysed vegetable protein; while egg may appear as egg albumen, egg yolk, or egg lecithin. Under Australian food labelling laws certain foods must be declared on food labels including foods that contain gluten, eggs, milk, nuts, peanuts, fish, and milk. The label must declare whether the food is used as an ingredient, as part of a compound ingredient, as a food additive or part of a food additive, or as a processing aid or part of a processing aid.


Both food allergies and intolerances can be frightening. If you suspect that you have a food allergy or intolerance you should visit your doctor for a medical diagnosis. For further information about food allergies and intolerances please visit a medical professional.



Share this featured content